185 research outputs found

    The TLR4/NFκB-Dependent Inflammatory Response Activated by LPS Is Inhibited in Human Macrophages Pre-Exposed to Amorphous Silica Nanoparticles

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    Amorphous silica nanoparticles (ASNP) are present in a variety of products and their biological effects are actively investigated. Although several studies have documented pro-inflammatory effects of ASNP, the possibility that they also modify the response of innate immunity cells to natural activators has not been thoroughly investigated. Here, we study the effects of pyrogenic ASNP on the LPS-dependent activation of human macrophages differentiated from peripheral blood monocytes. In macrophages, 24 h of pre-exposure to non-cytotoxic doses of ASNP markedly inhibited the LPS-dependent induction of pro-inflammatory (TNFα, IL-6) and anti-inflammatory cytokines (IL-10). The inhibitory effect was associated with the suppression of NFκB activation and the increased intracellular sequestration of the TLR4 receptor. The late induction of glutamine synthetase (GS) by LPS was also prevented by pre-exposure to ASNP, while GS silencing did not interfere with cytokine secretion. It is concluded that (i) macrophages exposed to ASNP are less sensitive to LPS-dependent activation and (ii) GS induction by LPS is likely secondary to the stimulation of cytokine secretion. The observed interference with LPS effects may point to a dampening of the acute inflammatory response after exposure to ASNP in humans

    Tissue distribution and acute toxicity of silver after single intravenous administration in mice: nano-specific and size-dependent effects

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    Background: Silver nanoparticles (AgNPs) are an important class of nanomaterials used as antimicrobial agents for a wide range of medical and industrial applications. However toxicity of AgNPs and impact of their physicochemical characteristics in in vivo models still need to be comprehensively characterized. The aim of this study was to investigate the effect of size and coating on tissue distribution and toxicity of AgNPs after intravenous administration in mice, and compare the results with those obtained after silver acetate administration. Methods: Male CD-1(ICR) mice were intravenously injected with AgNPs of different sizes (10 nm, 40 nm, 100 nm), citrate-or polyvinylpyrrolidone-coated, at a single dose of 10 mg/kg bw. An equivalent dose of silver ions was administered as silver acetate. Mice were euthanized 24 h after the treatment, and silver quantification by ICP-MS and histopathology were performed on spleen, liver, lungs, kidneys, brain, and blood. Results: For all particle sizes, regardless of their coating, the highest silver concentrations were found in the spleen and liver, followed by lung, kidney, and brain. Silver concentrations were significantly higher in the spleen, lung, kidney, brain, and blood of mice treated with 10 nm AgNPs than those treated with larger particles. Relevant toxic effects (midzonal hepatocellular necrosis, gall bladder hemorrhage) were found in mice treated with 10 nm AgNPs, while in mice treated with 40 nm and 100 nm AgNPs lesions were milder or negligible, respectively. In mice treated with silver acetate, silver concentrations were significantly lower in the spleen and lung, and higher in the kidney than in mice treated with 10 nm AgNPs, and a different target organ of toxicity was identified (kidney). Conclusions: Administration of the smallest (10 nm) nanoparticles resulted in enhanced silver tissue distribution and overt hepatobiliary toxicity compared to larger ones (40 and 100 nm), while coating had no relevant impact. Distinct patterns of tissue distribution and toxicity were observed after silver acetate administration. It is concluded that if AgNPs become systemically available, they behave differently from ionic silver, exerting distinct and size-dependent effects, strictly related to the nanoparticulate form

    In vitro bioaccessibility of macro and trace elements in biofortified and conventional farmed gilthead seabream (Sparus aurata) and common carp (Cyprinus carpio)

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    Biofortification is a promising strategy to improve the nutrient profile of farmed fish but requires consideration of the nutrient bioaccessible fraction. In this study, the in vitro bioaccessibility of macro and trace elements was investigated in biofortified and conventional farmed gilthead seabream and common carp, also taking into account the effect of cooking (by steaming). Biofortification enhanced iodine and selenium levels in seabream and carp fillets. Steaming increased iodine and selenium contents in biofortified seabream, and increased selenium and decreased copper levels in biofortified carp. Higher iodine bioaccessibilty (> 80%) was observed in biofortified seabream compared to biofortified carp (45%). In both species, selenium, iron, and zinc bioaccessibility was ≥ 70%. Upon steaming iodine and iron bioaccessibility decreased in seabream, while selenium bioaccessibility decreased in carp. The consumption of steamed biofortified seabream and carp contributes to significantly higher daily intakes of iodine (up to 12% and 10%, respectively) and selenium (up to 54% and above 100%, respectively) compared to conventional counterparts. The present study demonstrates the potential of developing innovative biofortified farmed fish using natural sustainable feed ingredients to improve the intake of important nutrients for human health.Highlights: - Iodine bioaccessibility is 80% in seabream and lower than 50% in carp. - Selenium, iron and zinc bioaccessibility were always above 70%. - Overall, bioaccessibility decreased after steaming (e.g., K: lower than 50%). - The availability of I and Se for absorption following the digestive process was higher in biofortified fillets.This work was supported by the European Union’s Horizon 2020 research and innovation programme under Grant Agreement no. 773400 (SEAFOODTOMORROW).info:eu-repo/semantics/publishedVersio

    Guidance for establishing and applying tolerable upper intake levels for vitamins and essential minerals:Draft for internal testing

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    Vitamins and essential minerals are micronutrients that are essential for the normal functioning of the human body. However, they may lead to adverse health effects if consumed in excess. The concept of a tolerable upper intake level (UL) is a science-based reference value, which was introduced to support policy-makers and other relevant actors in managing the risks of excess nutrient intake. EFSA\u2019s principles for establishing ULs for vitamins and minerals were originally developed by the Scientific Committee on Food in 2000. Since then, experience has been gained and the scientific field developed. This guidance from the EFSA Panel on Nutrition, Novel Foods and Food Allergens provides an updated framework to support EFSA\u2019s UL assessments. It covers aspects related to the planning of the risk assessment (problem formulation and definition of methods) and its implementation (evidence retrieval, appraisal, synthesis, integration, uncertainty analysis). As in the previous framework, the general principles developed for the risk assessment of chemicals in food are applied (hazard identification, hazard characterisation, intake assessment, risk characterisation). Peculiar to nutrients are their biochemical and physiological roles and the specific and selective mechanisms that maintain the systemic homoeostasis and body burden of the nutrient. These must be considered when conducting a risk assessment of nutrients. This document constitutes a draft guidance that will be applied in EFSA\u2019s assessments during a 1-year pilot phase and be revised and complemented as necessary. Before finalisation of the guidance, a public consultation will be launched

    Scientific opinion on the tolerable upper intake level for selenium

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    Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on the tolerable upper intake level (UL) for selenium. Systematic reviews of the literature were conducted to identify evidence regarding excess selenium intake and clinical effects and potential biomarkers of effect, risk of chronic diseases and impaired neuropsychological development in humans. Alopecia, as an early observable feature and a well‐established adverse effect of excess selenium exposure, is selected as the critical endpoint on which to base a UL for selenium. A lowest‐observed‐adverse‐effect‐level (LOAEL) of 330 μg/day is identified from a large randomised controlled trial in humans (the Selenium and Vitamin E Cancer Prevention Trial (SELECT)), to which an uncertainty factor of 1.3 is applied. A UL of 255 μg/day is established for adult men and women (including pregnant and lactating women). ULs for children are derived from the UL for adults using allometric scaling (body weight(0.75)). Based on available intake data, adult consumers are unlikely to exceed the UL, except for regular users of food supplements containing high daily doses of selenium or regular consumers of Brazil nuts. No risk has been reported with the current levels of selenium intake in European countries from food (excluding food supplements) in toddlers and children, and selenium intake arising from the natural content of foods does not raise reasons for concern. Selenium‐containing supplements in toddlers and children should be used with caution, based on individual needs

    Conversion of calcium-l-methylfolate and (6S)-5-methyltetrahydrofolic acid glucosamine salt into dietary folate equivalents

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    Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on the conversion of calcium-l-methylfolate and (6S)-5-methyltetrahydrofolic acid glucosamine salt (collectively called 5-MTHF hereafter) into dietary folate equivalents (DFE). Following a systematic review, the conclusions of the opinion are based on one intervention study in adults for intakes < 400 μg/day and three intervention studies in adults for intakes ≥ 400 μg/day. At intakes below 400 μg/day, folic acid (FA) is assumed to be linearly related to responses of biomarkers of intake and status and is an appropriate comparator for deriving a DFE conversion factor for 5-MTHF. It is proposed to use the same factor as for folic acid for conversion of 5-MTHF into DFE for intakes < 400 μg/day. As such intake levels are unlikely to be exceeded through fortified food consumption, the conversion factor of 1.7 relative to natural food folate (NF) could be applied to 5-MTHF added to foods and to food supplements providing < 400 μg/day. At 400 μg/day, 5-MTHF was found to be more bioavailable than folic acid and a conversion factor of 2 is proposed for this intake level and for higher intakes. The derived DFE equations are DFE = NF + 1.7 × FA + 1.7 × 5-MTHF for fortified foods and food supplements providing intakes < 400 μg/day; and DFE = NF + 1.7 × FA + 2.0 × 5-MTHF for food supplements providing intakes ≥ 400 μg/day. Although this assessment applies to calcium-L-methylfolate and 5-MTHF glucosamine salt, it is considered that the influence of the cation on bioavailability is likely to be within the margin of error of the proposed DFE equations. Therefore, the proposed equations can also be applied to 5-MTHF associated with other cations

    Safety of extended uses of UV-treated baker's yeast as a Novel Food pursuant to Regulation (EU) 2015/2283

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    In 2014, the EFSA NDA Panel concluded that UV-treated baker's yeast containing up to 3.5 Mio IU of vitamin D/100 g, is safe under the proposed conditions of use for yeast-leavened breads, rolls and fine bakery wares, and food supplements. Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on an application for an extension of the use of UV-treated baker's yeast as a novel food (NF) pursuant to Regulation (EU) 2015/2283. In this extension of use, the applicant proposed a broad range of food categories to which the NF can be added. On the basis of the proposed uses and maximum use levels, the Panel estimated the potential exposure to vitamin D from the NF and the potential combined exposure to vitamin D including also exposure from the background diet and food supplements. The Panel notes that the upper level (UL) for one age group, i.e. children aged 4-10 years, is exceeded by 4%, when summing up the highest P95 estimate for the background diet (including food supplements) and the highest P95 estimate for vitamin D from the NF under the proposed uses and maximum use levels. The Panel notes, however, the highly conservative approach for estimating the potential intake of vitamin D from the NF, given that the applicant has proposed 34 FoodEx2 level 2 food categories. Thus, the Panel considers that the UL for children aged between 4 and 10 years is highly unlikely to be exceeded. The Panel concludes that the NF is safe under the proposed conditions of use

    Safety of hydrothermally treated kernels from edible Jatropha curcas L. (Chuta) as a novel food pursuant to Regulation (EU) 2015/2283

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    [EN] Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on hydrothermally treated kernels from edible Jatropha curcas (Chuta) as a novel food (NF) pursuant to Regulation (EU) 2015/2283. Although Jatropha curcas is generally considered a toxic plant due to the presence of phorbol esters (PEs), edible varieties exist in Central America. The applicant has developed a breeding programme for an edible cultivar and proposes the kernels from this cultivar as an NF as whole kernels or fragments thereof to be used as a snack or as a food ingredient. Procedures are in place to avoid commingling with non-edible kernels, with the last steps being the analytical control of PEs concentrations in all produced batches. The Panel considers that the production process of the NF is sufficiently described and that the information provided on the composition of the NF is sufficient for its characterisation. Components of the NF were tested for genotoxicity applying the standard in vitro test battery and no genotoxic concerns have been identified. In a conservative scenario for exposure to PEs from the NF, it was assumed that all kernels contain PEs at the level of detection of the analytical method. When comparing the estimated maximum exposure to PEs with a reference point from a subchronic study in pigs, a margin of exposure ≥ 900 is obtained, which is considered sufficiently large. The presence of anti-nutritional factors does not pose safety concerns as they are within the ranges found in vegetables. The Panel concludes that the NF is safe under the proposed conditions of useSIThe Panel wishes to thank the Working Group on Compendium of Botanicals, Eirini Kouloura and Petra Gergelova for the support provided to this scientific outpu
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