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Introduction: Low dietary intake of vitamin E is a global public health issue. RRR-α-tocopherol (RRR-αT) is the only naturally occurring vitamin E stereoisomer, but the equimolecular mixture of all eight stereoisomers, synthetic vitamin E (S-αT), is commonly consumed. The objective of this study was to evaluate bioavailability and antioxidant activity of RRR-αT versus S-αT, in both mother and fetus, after maternal supplementation during pregnancy. Methods: Female rats (7 weeks of age) received a modified AIN-93G diet supplemented with 75 IU/kg of RRR-αT (NVE, n = 20) or S-αT (SVE, n = 17). At delivery, the levels of αT, stereoisomer distribution, and antioxidant capacity were analyzed in maternal and fetal plasma. Results: NVE administration significantly increased the proportion of RRR-αT stereoisomer in maternal and fetal plasma. The percentage of RRR-αT increased from 32.76% to 88.33% in maternal plasma, and 35.25% to 97.94% in fetal plasma, in the NVE group compared to SVE. Fetal plasma from the NVE group was found to have higher total antioxidant capacity compared to SVE. Lastly, fetal plasma RRR-αT stereoisomer percentage was positively associated with expression levels of scavenger receptor class B type 1 (SR-B1) in the placenta. Conclusions: Both natural and synthetic sources of vitamin E showed similar bioavailability. Still, NVE supplementation increased the proportion of RRR-αT and promoted higher antioxidant activity in fetal plasma at birth. Placental SR-B1 might be involved in the stereoselective transfer of RRR-αT stereoisomer across the placenta and may improve αT bioactivity in the fetus.

Background The cellular mechanisms underlying the age‐associated loss of muscle mass and function (sarcopenia) are poorly understood, hampering the development of effective treatment strategies. Here, we performed a detailed characterization of age‐related pathophysiological changes in the mouse neuromuscular system. Methods Young, adult, middle‐aged, and old (1, 4, 14, and 24-30 months old, respectively) C57BL/6J mice were used. Motor behavioural and electrophysiological tests and histological and immunocytochemical procedures were carried out to simultaneously analyse structural, molecular, and functional age‐related changes in distinct cellular components of the neuromuscular system. Results Ageing was not accompanied by a significant loss of spinal motoneurons (MNs), although a proportion (~15%) of them in old mice exhibited an abnormally dark appearance. Dark MNs were also observed in adult (~9%) and young (~4%) animals, suggesting that during ageing, some MNs undergo early deleterious changes, which may not lead to MN death. Old MNs were depleted of cholinergic and glutamatergic inputs (~40% and ~45%, respectively, P < 0.01), suggestive of age‐associated alterations in MN excitability. Prominent microgliosis and astrogliosis [~93% (P < 0.001) and ~100% (P < 0.0001) increase vs. adults, respectively] were found in old spinal cords, with increased density of pro‐inflammatory M1 microglia and A1 astroglia (25‐fold and 4‐fold increase, respectively, P < 0.0001). Ageing resulted in significant reductions in the nerve conduction velocity and the compound muscle action potential amplitude (~30%, P < 0.05, vs. adults) in old distal plantar muscles. Compared with adult muscles, old muscles exhibited significantly higher numbers of both denervated and polyinnervated neuromuscular junctions, changes in fibre type composition, higher proportion of fibres showing central nuclei and lipofuscin aggregates, depletion of satellite cells, and augmented expression of different molecules related to development, plasticity, and maintenance of neuromuscular junctions, including calcitonin gene‐related peptide, growth associated protein 43, agrin, fibroblast growth factor binding protein 1, and transforming growth factor‐β1. Overall, these alterations occurred at varying degrees in all the muscles analysed, with no correlation between the age‐related changes observed and myofiber type composition or muscle topography. Conclusions Our data provide a global view of age‐associated neuromuscular changes in a mouse model of ageing and help to advance understanding of contributing pathways leading to development of sarcopenia. This work was supported by Abbott and a grant from the Ministerio de Ciencia, Innovación y Universidades cofinancedby Fondo Europeo de Desarrollo Regional (RTI2018-099278-B-I00 to J.C. and J.E.)

Alzheimer's disease and Type 2 diabetes are pathological processes associated to ageing. Moreover, there are evidences supporting a mechanistic link between Alzheimer's disease and insulin resistance (one of the first hallmarks of Type 2 diabetes). Regarding Alzheimer's disease, amyloid β-peptide aggregation into β-sheets is the main hallmark of Alzheimer's disease. At monomeric state, amyloid β-peptide is not toxic but its function in brain, if any, is unknown. Here we show, by in silico study, that monomeric amyloid β-peptide 1-40 shares the tertiary structure with insulin and is thereby able to bind and activate insulin receptor. We validated this prediction experimentally by treating human neuroblastoma cells with increasing concentrations of monomeric amyloid β-peptide 1-40. Our results confirm that monomeric amyloid β-peptide 1-40 activates insulin receptor autophosphorylation, triggering downstream enzyme phosphorylations and the glucose Transporter 4 translocation to the membrane. On the other hand, neuronal insulin resistance is known to be associated to Alzheimer's disease since early stages. We thus modelled the docking of oligomeric amyloid β-peptide 1-40 to insulin receptor. We found that oligomeric amyloid β-peptide 1-40 blocks insulin receptor, impairing its activation. It was confirmed in vitro by observing the lack of insulin receptor autophosphorylation, and also the impairment of insulin-induced intracellular enzyme activations and the glucose Transporter 4 translocation to the membrane. By biological system analysis, we have carried out a mathematical model recapitulating the process that turns amyloid β-peptide binding to insulin receptor from the physiological to the pathophysiological regime. Our results suggest that monomeric amyloid β-peptide 1-40 contributes to mimic insulin effects in the brain, which could be good when neurons have an extra requirement of energy beside the well-known protective effects on insulin intracellular signalling, while its accumulation and subsequent oligomerization blocks the insulin receptor producing insulin resistance and compromising neuronal metabolism and protective pathways. This work was supported by the Spanish Ministry of Science and Innovation and Agencia Estatal de Investigación plus European Regional Development Fund (FEDER Funds) through grants PID2020-117691RB-I00/AEI/10.13039/501100011033 (F.J.M.), SAF2017-83372-R (F.J.M.), BIO2017-85329-R (B.O.), PGC2018-101251-B-I00 (J.G.-O.) and RTI2018-094579-B-I00 (X.F.-B.). This work was also funded by the Spanish Institute of Health Carlos III by project reference AC20/00009 -FEDER/UE and European Research Era Net (ERANET) ERA-CVD_JTC2020-015 (J.G.-O.), by the ‘María de Maeztu Programme’ for Units of Excellence in Research and Development (R&D; award CEX2018-000792-M), Generalitat de Catalunya (Spain) through the grant 2017-SGR-908 (X.F.-B.) and Fundación QUAES through Cátedra QUAES-UPF de Biomedicina e Ingeniería Biomédica. The Instituto de Salud Global de Barcelona (ISGlobal) and Institute for Bioengineering of Catalonia (IBEC) are members of the Centres de Recerca de Catalunya (CERCA) Programme, Generalitat de Catalunya (Spain). We acknowledge support from the Spanish Ministry of Science, Innovation and Universities through the ‘Centro de Excelencia Severo Ochoa 2019–2023’ Programme (CEX2018-000806-S). This research is part of ISGlobal's Programme on the Molecular Mechanisms of Malaria, which is partially supported by the Fundación Ramón Areces. J.G.-O. also acknowledges support from the Institució Catalana de Recerca i Estudis Avançats (ICREA) Academia programme.

This work was supported by Abbott and a grant from the Spanish Ministerio de Ciencia, Innovacion y Universidades cofinanced by Fondo Europeo de Desarrollo Regional (RTI2018-099278-B-I00 to JC and JE) ., Besides skeletal muscle wasting, sarcopenia entails morphological and molecular changes in distinct components of the neuromuscular system, including spinal cord motoneurons (MNs) and neuromuscular junctions (NMJs); moreover, noticeable microgliosis has also been observed around aged MNs. Here we examined the impact of two flavonoid-enriched diets containing either green tea extract (GTE) catechins or cocoa flavanols on age-associated regressive changes in the neuromuscular system of C57BL/6J mice. Compared to control mice, GTE- and cocoa-supplementation significantly improved the survival rate of mice, reduced the proportion of fibers with lipofuscin aggregates and central nuclei, and increased the density of satellite cells in skeletal muscles. Additionally, both supplements significantly augmented the number of innervated NMJs and their degree of maturity compared to controls. GTE, but not cocoa, prominently increased the density of VAChT and VGluT2 afferent synapses on MNs, which were lost in control aged spinal cords; conversely, cocoa, but not GTE, significantly augmented the proportion of VGluT1 afferent synapses on aged MNs. Moreover, GTE, but not cocoa, reduced aging-associated microgliosis and increased the proportion of neuroprotective microglial phenotypes. Our data indicate that certain plant flavonoids may be beneficial in the nutritional management of age-related deterioration of the neuromuscular system., Abbott Laboratories, Spanish Ministerio de Ciencia, Innovacion y Universidades, European Commission RTI2018-099278-B-I00

Alzheimer's disease (AD) is tightly linked to oxidative stress since amyloid beta-peptide (Aβ) aggregates generate free radicals. Moreover, the aggregation of Aβ is increased by oxidative stress, and the neurotoxicity induced by the oligomers and fibrils is in part mediated by free radicals. Interestingly, it has been reported that oxidative stress can also induce BACE1 transcription and expression. BACE1 is the key enzyme in the cleavage of the amyloid precursor protein to produce Aβ, and the expression of this enzyme has been previously shown to be enhanced in the brains of Alzheimer's patients. Here, we have found that BACE1 expression is increased in the hippocampi from AD patients at both the early (Braak stage II) and late (Braak stage VI) stages of the disease as studied by immunohistochemistry and western blot. To address the role of Aβ and oxidative stress in the regulation of BACE1 expression, we have analyzed the effect of subtoxic concentrations of Aβ oligomers (0.25 μM) and H2O2 (10 mM) on a human neuroblastoma cell line. Firstly, our results show that Aβ oligomers and H2O2 induce an increase of BACE1 mRNA as we studied by qPCR. Regarding BACE1 translation, it is dependent on the phosphorylation of the eukaryotic initiation factor 2α (eIF2α), since BACE1 mRNA bears a 5′UTR that avoids its translation under basal conditions. BACE1 5′UTR contains four upstream initiating codons (uAUGs), and its translation is activated when eIF2α is phosphorylated. Consistently, we have obtained that Aβ oligomers and H2O2 increase the levels of BACE1 and p-eIF2α assayed by western blot and confocal microscopy. Our results suggest that Aβ oligomers increase BACE1 translation by phosphorylating eIF2α in a process that involves oxidative stress and conforms a pathophysiological loop, where the Aβ once aggregated favors its own production continuously by the increase in BACE1 expression as observed in AD patients., Spanish Ministry of Economy and Business through the grant Plan Estatal SAF2017-83372-R and SAF2014-52228-R (FEDER funds/UE) to FJM and RV, Chilean Government through Fondecyt 11611065 and AFB170005 to AA and REDES 180084 to AA and FJM, and MDM-2014-0370 through the María de Maeztu Programme for Units of Excellence in R&D to Departament de Ciències Experimentals i de la Salut. Silvia Menéndez is supported by the Health Deparment of the Generalitat de Catalunya, Spain

The risk posed by microplastics for human and environment, has become a hot topic. The concern is focused not only on the effect of microplastics as such but also on additives and chemical contaminants absorbed by microplastics that may be released and affect negatively animals and environmental health. Despite several works have been written on this topic, a number of knowledge gaps still should be filled to enable a correct risk assessment of this important issue. For example, the relevance of microplastics for food safety has not yet been fully established and scientific results aimed at establishing a possible health risk for contaminants associated with microplastics are rather controversial. The risk assessment of microplastics in foodstuff is still at a very early stage and very few studies on the monitoring of microplastics in foodstuff and their effects on human health are available. Additionally, it is difficult to compare results from different studies as methodologies and study designs are not uniform. For this reason, it is not always possible to reach some definitive conclusion. This work sets out to complement the reviews and statements already existing, by updating the information and identifying if any of the knowledge gaps have been covered and if further ones have been detected with the final aim of properly assessing and managing this emerging risk.

Mercury still represents one of the most hazardous threats for the aquatic ecosystem due to its high toxicity, and the fact that it can be easily incorporated into the food chain by accumulation in fish as MeHg. On the other hand, selenium is a micronutrient that is part of different antioxidant enzymes that regulate the cellular redox state, and whose complex interaction with Hg has been extensively studied from a toxicological point of view. In order to evaluate the protective effect of Se(IV) co-administration against MeHg accumulation and toxicity, we have selected an in-vivo model at two developmental stages: zebrafish eleutheroembryos and adult fish. Embryos were exposed during 48 h to MeHg (5 or 25 μg/l) and a concentration of Se (IV) representing a molar ratio close to one (2.5 or 12.5 μg/l), while adult zebrafish were exposed during 72 h to either 25 μg/l of MeHg alone or co-exposed with 12.5 μg/l of Se (IV). A significant decrease in MeHg bioaccumulation factor was observed in eleutheroembryos co-exposed to Se(IV). A time-dependent accumulation of MeHg was observed in all the analyzed organs and tissues of adult fish, which was significantly reduced in the muscular tissue and the intestine by Se(IV) co-administration. However, such protection against MeHg bioaccumulation was not maintained in the brain and liver. The data derived from the gene expression analysis also demonstrated the protective effect of Se(IV) against MeHg-induced oxidative stress and the activation of different defense mechanisms by Se(IV) co-administration.

Background Zebrafish have been increasingly used for monitoring and assessing the effects of different contaminants in the aquatic environments. In the present study, zebrafish embryos and larvae were used to study the effects of the insecticide diazinon and the herbicide diuron in regard to occurrence of oxidative stress-related cellular responses, multixenobiotic resistance (MXR)-related efflux transporter activity—which represents the first line of defense against xenobiotics in many aquatic organisms—and responses of different molecular and biochemical biomarkers. Results The recently established non-invasive quantitative plate assay, which uses the fluorescent probes CM-H2DCFDA and CellTracker™ Green CMFDA and measures the fluorescence in whole zebrafish larvae, was applied to assess changes in reactive oxidative species (ROS) and glutathione (GSH) after exposure to the investigated pesticides. The results showed a significant increase of GSH after 1h exposure of zebrafish larvae to both diazinon and diuron. Regarding the ROS induction, no significant increases in fluorescence could be detected after 2h exposure to the investigated pesticides. Applying a newly adapted assay for MXR activity, it was determined that diuron caused no change after a 24-h exposure, but caused a significant induction of MXR activity after a 48-h exposure (indicated by a decreased amount of accumulated rhodamine B). On the other hand, diazinon caused an inhibition of MXR activity after both 24h and 48h exposure (indicated by an increased amount of accumulated rhodamine B). Regarding the biomarkers, different set-ups and exposure periods were applied and both molecular (gene expression) and biochemical (enzymatic activities) responses were assessed. Diazinon caused an inhibition of carboxylesterase (CES) and acetylcholinesterase (AChE) activity in zebrafish larvae, diuron inhibited AChE activity in in vitro testing, and both pesticides significantly affected gene expression and activities of some of the cytochrome P450 (CYP) family enzymes. Conclusions The obtained results show various effects of the investigated pesticides and will help to elucidate how aquatic animals cope with pesticides present in their environment. Additionally, the recently developed fluorescence-based assay and the newly adapted MXR activity assay proved to be useful tools for ecotoxicological risk assessment to further investigate pesticide effects.

Food safety is embedded in food-related problems, and in proposed solutions. Despite continuous investment, the WHO estimates 23 million cases of foodborne illness and 5000 deaths in Europe every year and Europeans are not confident in the food system. Now, the circular economy aims to improve global food security through sustainable production, thus new ingredients, methods and food safety challenges. Food is unequivocally linked to non-communicable diseases, and changes are needed for nutritional food safety. Emerging and re-emerging foodborne pathogens are changing the epidemiology of foodborne diseases. Additionally, some chemicals are of concern, and food is a major source of human exposure. Finally, risk communication is required for management of consumer-based foodborne hazards, yet this foodborne illness is common. We ignore food safety challenges at our peril as potential consequences of a lapse are huge; keeping the food supply safe is a never-ending task.

In this study we evaluated the exposure effects of mixtures of five polycyclic aromatic hydrocarbons (PAHs); namely, benzo[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene and chrysene on zebrafish embryos. Supplementation of the exposure media with 0.45% dimethyl sulfoxide and 50 ppm of Tween 20 could guarantee the solubilization and stabilization of the PAHs up to 24 h without affecting the embryos development. The exposure effects were tested by detecting the differential expression of a number of genes related to the aryl hydrocarbon receptor gene battery. Effects were detectable already after 6 h of exposure. After 24 h of exposure, all PAHs, except for benzo[a]anthracene, acted as potent inducers of the gene cyp1a1. Benzo[k]fluoranthene was the major inducer; the effect caused by the mixture at the lower concentration tested (1 ng ml-1 ) was dominated by its presence. However, in the mixture at the highest concentration tested (10 ng ml-1 ) it caused less induction and was not dominant. No significant bioaccumulation values were detected on embryos exposed to the PAHs tested in this study; however, the results obtained, indicated that PAHs undergo a very rapid metabolization inside the embryos, and that those biotransformation products yield changes on the expression of genes involved in the aryl hydrocarbon receptor pathway. Future work should focus on identification of the PAH metabolization products and on the effect of these metabolites on toxicity. Copyright © 2016 John Wiley & Sons, Ltd.

A novel multianalyte method has been developed to determine the concentration of trimethylamine (TMA), dimethylamine (DMA) and methylamine (MA) in fish. The optimal points of the key parameters (pH 8, 60 °C and 60 min of reaction time) were determined for the reaction with tert-butyl bromoacetate. An HILIC column was used to elute all the compounds in only 12 min and selective quantitation of the compounds was achieved. The methodology was validated in trout, hake and Atlantic horse mackerel and was used to study the shelf life of fish under refrigeration. A good correlation with the picrate method was obtained and the proposed methodology has been proved to be robust, specific and sensible with a limit of detection of 0.08 mg N-TMA kg(-1) in freshwater fish and 1 mg N-TMA kg(-1) in marine fish. In addition, TMA has been proved to be a good spoilage indicator also in freshwater fish.

Sialic acids (Sia) are postulated to improve cognitive abilities. This study evaluated Sia effects on rat behavior when administered in a free form as N-acetylneuraminic acid (Neu5Ac) or conjugated as 6&prime, sialyllactose (6&prime, SL). Rat milk contains Sia, which peaks at Postnatal Day 9 and drops to a minimum by Day 15. To bypass this Sia peak, a cohort of foster mothers was used to raise the experimental pups. A group of pups received a daily oral supplementation of Neu5Ac to mimic the amount naturally present in rat milk, and another group received the same molar amount of Sia as 6&prime, SL. The control group received water. After weaning, rats were submitted to behavioral evaluation. One year later, behavior was re-evaluated, and in vivo long-term potentiation (LTP) was performed. Brain samples were collected and analyzed at both ages. Adult rats who received Sia performed significantly better in the behavioral assessment and showed an enhanced LTP compared to controls. Within Sia groups, 6&prime, SL rats showed better scores in some cognitive outcomes compared to Neu5Ac rats. At weaning, an effect on polysialylated-neural cell adhesion molecule (PSA-NCAM) levels in the frontal cortex was only observed in 6&prime, SL fed rats. Providing Sia during lactation, especially as 6&prime, SL, improves memory and LTP in adult rats.

The objective of this work was to highlight the importance of testing in a realistic way, metallic nanoparticles-based products, used in the food sector in order to provide representative data for a realistic and accurate risk assessment. To this end we give a brief overview of the current use and applications of metallic nanoparticles in the food industry, how the toxicological evaluations of nanoparticles in food should be performed and how nanoparticles-based products are regulated worldwide.This brief overview work provides a picture of the latest issues on the safety evaluation of metallic nanoparticles in the food sector and identifies also some major points that are important to take into consideration for future studies.El objetivo de este trabajo fue resaltar la importancia de analizar de forma realista los productos que contienen nanopartículas metálicas utilizados en el sector alimentario a fin de proporcionar datos representativos para una evaluación de riesgos realista y precisa. Con este fin, presentamos una breve descripción del uso y de las aplicaciones actuales de las nanopartículas metálicas en la industria alimentaria, cómo deben realizarse sus evaluaciones toxicológicas en los alimentos y cómo están regulados los productos de nanopartículas a nivel internacional. Este breve trabajo general proporciona una visión de los problemas más actuales sobre la evaluación de la seguridad de las nanopartículas metálicas en el sector alimentario e identifica también algunos puntos importantes a tener en cuenta para futuros estudios.

The modes of action of pollutants are diverse, and a common consequences to pollutant exposure is oxidative stress. This phenomenon is caused by an imbalance or disurption in the control of Reactive Oxygen Species (ROS) resulting in an accumulation of free radicals. Oxidative stress may cause damages to the DNA, phospholipids and proteins, and lead to cell death. Due to the possible contribution of oxidative stress to pollutant toxicity , it is valuable to assess its occurrence, role and mechanism. Detection of oxidative stress at low concentrations soon after the onset of exposure can be a sensitive, general marker for contamination. This study aimed at developing and benchmarking a set of novel fluorescence-based procedures to assess the occurrence of oxidative stress in zebrafish larvae (96 hpf) by measuring the antioxidant glutathione (GSH) and general ROS. Zebrafish larvae were exposed to tert-butyl hydroperoxide (t-BHP). ROS and GSH were made visible by means of specific fluorescent molecular probes in different experimental scenarios. The induction was qualified using microscopy and quantified through photometric measurement. For quantitative assessment, an approach based on homogenized larvae and a non-invasive plate assay were developed. The novel procedures proved suitable for oxidative stress detection. Comparisons of qualitative to quantitative data showed that the orientation of the larvae in the well can influence fluorescence data evaluation. The non-invasive quantitative assay proved robust against any influence of the orientation of the larvae. The developed protocols promise to be useful tools for the detection of oxidative stress in zebrafish larvae.

Human milk oligosaccharides (HMOs) are unique with regard to their diversity, quantity and complexity, particularly in comparison to bovine milk oligosaccharides. HMOs are associated with functional development during early life, mainly related to immunity and intestinal health. Whether HMOs elicit a positive effect on cognitive capabilities of lactating infants remains an open question. This study evaluated the role of the most abundant HMO, 2′-fucosyllactose (2′-FL), in synaptic plasticity and learning capabilities in rodents. Mice and rats were prepared for the chronic recording of field excitatory postsynaptic potentials evoked at the hippocampal CA3–CA1 synapse. Following chronic oral administration of 2′-FL, both species showed improvements in input/output curves and in long-term potentiation (LTP) evoked experimentally in alert behaving animals. This effect on LTP was related to better performance of animals in various types of learning behavioral tests. Mice were tested for spatial learning, working memory and operant conditioning using the IntelliCage system, while rats were submitted to a fixed-ratio schedule in the Skinner box. In both cases, 2′-FL-treated animals performed significantly better than controls. In addition, chronic administration of 2′-FL increased the expression of different molecules involved in the storage of newly acquired memories, such as the postsynaptic density protein 95, phosphorylated calcium/calmodulin-dependent kinase II and brain-derived neurotrophic factor in cortical and subcortical structures. Taken together, the data show that dietary 2′-FL affects cognitive domains and improves learning and memory in rodents.

Microplastics contamination of the aquatic environment is considered a growing problem. The ingestion of microplastics has been documented for a variety of aquatic animals. Studies have shown the potential of microplastics to affect the bioavailability and uptake route of sorbed co-contaminants of different nature in living organisms. Persistent organic pollutants and metals have been the co-contaminants majorly investigated in this field. The combined effect of microplastics and sorbed co-contaminants in aquatic organisms still needs to be properly understood. To address this, we have subjected zebrafish to four different feeds: A) untreated feed; B) feed supplemented with microplastics (LD-PE 125–250 µm of diameter); C) feed supplemented with 2% microplastics to which a mixture of PCBs, BFRs, PFCs and methylmercury were sorbed; and D) feed supplemented with the mixture of contaminants only. After 3 weeks of exposure fish were dissected and liver, intestine, muscular tissue and brain were extracted. After visual observation, evaluation of differential gene expression of some selected biomarker genes in liver, intestine and brain were carried out. Additionally, quantification of perfluorinated compounds in liver, brain, muscular tissue and intestine of some selected samples were performed. The feed supplemented with microplastics with sorbed contaminants produced the most evident effects especially on the liver. The results indicate that microplastics alone does not produce relevant effects on zebrafish in the experimental conditions tested; on the contrary, the combined effect of microplastics and sorbed contaminants altered significantly their organs homeostasis in a greater manner than the contaminants alone.

Resveratrol, a polyphenolic phytoalexin found in many plants, has been reported to have antiobesogenic effects in several animal and in vitro models. Zebrafish present several technical advantages that place them at an interesting, halfway point between in vitro and rodent models. The aim of the present work was to evaluate the metabolization of resveratrol and its glucoside (piceid) in zebrafish and their ability to induce the consumption of fat reserve in zebrafish larvae. Resveratrol and piceid were both able to reduce yolk sac fat content depending on the dose tested. Furthermore, resveratrol showed a potent and rapid action, whereas piceid needed more time and higher doses to be as effective as resveratrol. In accordance with other animal models and humans, the principal metabolites found in zebrafish larvae were monoglucoronide and monosulfate forms of resveratrol. In conclusion, zebrafish are a potentially excellent animal model for polyphenol research as they present several advantageous characteristics for efficacy screening and metabolomic studies before rodents.

A variety of consumer products containing silver nanoparticles (Ag NPs) are currently marketed. However, their safety for humans and for the environment has not yet been established and no standard method to assess their toxicity is currently available. The objective of this work was to develop an effective method to test Ag NP toxicity and to evaluate the effects of ion release and Ag NP size on a vertebrate model. To this aim, the zebrafish animal model was exposed to a solution of commercial nanosilver. While the exposure of embryos still surrounded by the chorion did not allow a definite estimation of the toxic effects exerted by the compound, the exposure for 48 h of 3-day-old zebrafish hatched embryos afforded a reliable evaluation of the effects of Ag NPs. The effects of the exposure were detected especially at molecular level; in fact, some selected genes expressed differentially after the exposure. The Ag NP toxic performance was due to the combined effect of Ag(+) ion release and Ag NP size. However, the effect of NP size was particularly detectable at the lowest concentration of nanosilver tested (0.01 mg l(-1)) and depended on the solubilization media. The results obtained indicate that in vivo toxicity studies of nanosilver should be performed with ad hoc methods (in this case using hatched embryos) that might be different depending on the type of nanosilver. Moreover, the addition of this compound to commercial products should take into consideration the Ag NP solubilization media.

Background Atlantic horse mackerel (Trachurus trachurus) is an important commercial fish in Europe. Changes in microbial growth, sensory quality and chemical evolution of modified atmosphere packed (MAP) horse mackerel fillets (48% CO2/50% N2/2% O2) were monitored at different storage temperatures (2, 4, 6 and 10 °C). Results The observed sensory shelf life of MAP fish fillets was found to be approximately 7 days at 2 °C, 6 days at 4 °C, 5 at 6 °C and 3 days at 10 °C. A significant correlation was observed between all sensory attributes and two groups of bacteria [total viable count (TVC) and psychrotrophic bacteria], with sensorial rejection when the bacteria approached 106 CFU g−1 at 4, 6 and 10 °C. A level of 30–50 mg total volatile basic nitrogen 100 g−1 of mackerel muscle was well correlated with sensory shelf life determination at all temperatures, except for 2 °C. During the storage time, lipid oxidation did not increase at any temperature and could not be related to quality decay. The presence of acetaldehyde and butyraldehyde in the packing atmosphere was only found in fillets stored at the highest temperature studied (10 °C). Conclusion In this study, key quality parameters were established to monitor the spoilage and shelf life of MAP Trachurus trachurus stored at different temperatures. In addition, these results confirm the use of modified atmosphere packaging as a mild preservation method for fillets of Atlantic horse mackerel. © 2012 Society of Chemical Industry

Emerging chemical contaminants in the marine ecosystem represent a threat to the environment and also to human health due to insufficient knowledge about their toxicity and bioaccumulation in the food chain. Consequently, many of them are not regulated. In this review we focus on musks and organic UV filters. For both groups of compounds we describe occurrence in the marine environment, toxic effects identified so far and methods used to identify such effects. The final objective of this work is to identify gaps in the understanding of their toxicology.

This work aims at deepening the understanding of the mode of action of some of the most prominent perfluorinated compounds (PFCs) by detecting in a realistic way their effects. To this end, after adjusting the exposure media taking into account the biological model employed and the physico-chemical properties of PFCs, we evaluated the toxic effects of PFOA, PFOS and PFNA in a human macrophage cell line (TLT cells) and in zebrafish embryos. We performed such evaluation on individual compounds and mixtures. Acute toxicity was greater for PFOS in zebrafish; however, it was greater for PFNA in TLT cells. PFNA was also the compound producing the greatest levels of oxidative stress, both in zebrafish and TLT cells. Additionally, in both biological systems, it showed a much stronger effect on mixtures in comparison to the others PFCs tested in this work. Mixture studies in zebrafish showed that acute toxicity depended on the concentration and that the mixture was far more toxic than the individual compounds. This study highlights the importance of studying PFCs in realistic conditions on various biological models.

Pathogenic agents (bacteria, fungi and viruses) and their toxins, and chemical toxicants (both from processing and from environmental sources) continue to be a major European public health concern. The re-introduction of discarded fractions into the food chain, the search for new protein sources, and the introduction of new species in the diet are examples of changes bringing new challenges to food safety specialists. Europe's progress towards a bio-based circular economy and novel sustainable technologies which limit environmental degradation pose unique risks, and consumer confidence in the ever-changing food sector will require scientific action, appropriate communication and holistic legislation. Rapid, sensitive and validated methods to detect pathogens and chemicals in food matrices are needed. The pathobiome concept, i.e. "the pathogenic agent integrated within its biotic environment" is a new and holistic way of looking at the complexities of contaminants all along the complex food chain. The use of omics technologies is increasing worldwide and now, the foodomics approach is here and it requires refinement, standardization and validated protocols. We need a food and agriculture system that has safe, healthy nutrition of the citizen and sustainability of resources as its major aims, remembering that food cannot be healthy and nutritious if it is not safe. Producing safe food for the future is a continual challenge in a constantly changing environment with ever increasing complexity of the European food basket. In the periods between newsworthy food safety outbreaks, the general sense of public awareness of the safety of food, and even perhaps official vigilance, may start to fade. This is a tremendous risk and one that we aim to avoid. Keeping food safety relevant requires awareness - we must keep food safety and food safety research high on the European agenda.

Meat and seafood chemical contaminants can be very dangerous for human health. The way in which food chemical contaminants are currently controlled is not optimal as the food cooking, processing and eating habits are generally not considered by authorities. The current review discusses the available information related to the toxicity of the most relevant meat and seafood chemical contaminants, their bioaccessibility after cooking or processing, and the implications for human health. In addition, the current in vivo toxicity and alternative tests carried out for testing the effects of food chemical contaminants are illustrated, as well as new detection tools. The use of non-carcinogenic functional cell models, of alternative animal models like zebrafish embryos, and a toxicogenomic approach seem to be the most promising strategy for the toxicity assessment of food chemical contaminants.

Human milk oligosaccharides have been proposed to exert beneficial effects on brain development. During the last decades, most of the studies have focused on the evaluation of sialylated structures but recent experiments have also tested fucosylated oligosaccharides, i.e. 2′-fucosyllactose (2′-FL). The present study aimed to determine whether oral 2′-FL has an effect on the development of newborn brain, contributing to enhance cognitive skills later in life. Rat pups received an oral supplementation of 2′-FL (2′-FL group) or water (control group) during the lactation period. Thereafter, animals were maintained on a rodent standard diet. Rats ( n = 12 rats/group) were evaluated twice, at age 4–6 weeks and again at age 1 year, using classical behavioral tests. In vivo long-term potentiation (LTP) was also performed at the same ages ( n = 10 rats/group). Both groups showed similar behavior when the animals were assessed just after weaning (age 4–6 weeks), although the 2′-FL group seemed to perform slightly better in Morris Water Maze. At age 1 year, 2′-FL rats performed significantly better in the Novel Object Recognition and Y maze paradigms, when compared to controls. In addition, LTP was more intense and longer lasting in the rats supplemented with 2′-FL than in control animals, both in young and adult animals. Oral administration of 2′-FL exclusively during lactation enhanced cognitive abilities, not only in childhood but also in adulthood.

In this study we evaluated the exposure effects of mixtures of five polycyclic aromatic hydrocarbons (PAHs); namely, benzo[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene and chrysene on zebrafish embryos. Supplementation of the exposure media with 0.45% dimethyl sulfoxide and 50 ppm of Tween 20 could guarantee the solubilization and stabilization of the PAHs up to 24 h without affecting the embryos development. The exposure effects were tested by detecting the differential expression of a number of genes related to the aryl hydrocarbon receptor gene battery. Effects were detectable already after 6 h of exposure. After 24 h of exposure, all PAHs, except for benzo[a]anthracene, acted as potent inducers of the gene cyp1a1. Benzo[k]fluoranthene was the major inducer; the effect caused by the mixture at the lower concentration tested (1 ng ml

Polyphenolic compositions of Basque natural ciders were determined by high-performance liquid chromatography, with diode array detection following thiolysis, in order to differentiate ciders according to the geographical origin of the main raw material used for their elaboration. Fifty percent of the apples used for cidermaking in the Basque Country are imported from France or Galicia (N.W. Spain); this gives beverages of different chemical compositions and sensory qualities. A data set, consisting of 64 cider samples and 33 measured variables, was evaluated using multivariate chemometric techniques. A preliminary study of data structure was performed by cluster analysis and principal component analysis. Different classification systems for the two categories were obtained on the basis of the chemical data by applying several supervised pattern recognition procedures, such as linear discriminant analysis (LDA), K-nearest neighbours (KNN), soft independent modelling of class analogy (SIMCA), and multilayer feed-forward artificial neural networks (MLF-ANN). KNN, SIMCA and the MLF neural network provided complementary results: KNN allowed the correct classification of almost all the ciders of the Galician category, SIMCA provided a model for the ciders of the French category that excluded all ciders made with Galician apples (50% of raw material), and the neural network achieved a level of hits for the classification of the ciders obtained from French apples (50% of raw material) above 95%. Polyphenolic profiles of the ciders provide enough information to develop classification rules for identifying ciders according to the geographical origin of the raw material used for cidermaking.

Polyphenolic profiles of cider apple cultivars were studied in order to differentiate fruits according to their maturity state (ripe or unripe). Thiolysis and direct solvent extracts of freeze-dried apple pulps and peels were analysed by HPLC-DAD. Univariate data treatment did not achieve the mentioned target; thus a multivariate approach was considered. For each apple tissue data set, several chemometric techniques were applied to the most discriminant variables. Cluster analysis allowed a preliminary study of the data structure. Then, supervised pattern recognition procedures, namely linear discriminant analysis, K-nearest neighbours, soft independent modelling of class analogy, and multilayer feed-forward artificial neural networks (MLF-ANN), were used to develop decision rules to classify samples in the established categories. Excellent results were afforded by MLF-ANN applied to the concentrations of total procyanidins and (+)-catechin and the average degree of polymerisation of procyanidins in apple pulp, with success in the prediction ability of 97% and 99% for unripe and ripe categories, respectively.

A solid–liquid extraction procedure followed by reversed-phase high-performance liquid chromatography (RP-HPLC) coupled with a photodiode array detector (DAD) for the determination of polyphenols in freeze-dried apple peel and pulp is reported. The extraction step consists in sonicating 0.5 g of freeze-dried apple tissue with 30 mL of methanol–water–acetic acid (30:69:1, v/v/v) containing 2 g of ascorbic acid/L, for 10 min in an ultrasonic bath. The whole method was validated, concluding that it is a robust method that presents high extraction efficiencies (peel: >91%, pulp: >95%) and appropriate precisions (within day: R.S.D. (n = 5)

Two methods for clean-up and sample enrichment for the analysis of polycyclic aromatic hydrocarbons (PAHs) in edible oils are compared; a clean-up based on a donor–acceptor complex chromatography (DACC) column and a standardized method widely used in the food industry consisting in a low pressure column chromatography with alumina as stationary phase. Both methods are followed by a reversed-phase high-performance liquid chromatography with fluorescence detection for the separation and quantitation of each PAH. Certified materials were used in order to validate the methods. The limits of detection were lower than 1 ng/g and good selectivity was achieved in both cases. The DACC column clean-up is faster and better accuracies were obtained. The advantages and disadvantages of both methods are discussed.

The polyphenolic compositions of 31 Basque cider apple cultivars were determined in pulp, peel, and juice by high-performance liquid chromatography with diode array detection analysis of crude extracts and after thiolysis. Total polyphenols are distributed in a wide concentration range depending on the cultivar. Procyanidins are the class of polyphenols that present major concentrations in apple. Their average degrees of polymerization range from 4 to 8 depending on the cultivar. Apple cultivars were technologically classified into bitter and nonbitter categories using different classification systems obtained by applying several pattern recognition techniques, such as principal component analysis, K-nearest neighbors, soft independent modeling of class analogy, partial least-squares, and multilayer feed-forward-artificial neural networks, to apple pulp, peel, or juice data (individual polyphenol concentrations, total procyanidin content, and the average degree of polymerization of procyanidins). Bitter apple cultivars present higher contents of flavan-3-ols and/or dihydrochalcones than nonbitter cultivars. Detailed knowledge of the polyphenolic profile of each apple cultivar affords information about their susceptibility to oxidation, their sensory properties (bitterness, astringency), and their possible influence on the characteristics and quality of the final product (juice, cider) when apples are processed.

An off-line high-performance normal-phase liquid chromatography procedure with a silica column followed by reversed-phase high-performance liquid chromatography (HPLC) with fluorescence detection for the determination of polycyclic aromatic hydrocarbons (PAHs) in edible oils is reported. The method was validated using certified reference materials and compared with a standardized method widely used in the food industry, consisting in low pressure column chromatography with alumina as stationary phase followed by reversed phase HPLC determination. The limits of detection were lower than 1 ng/g and good selectivity was achieved for both methods. There were no significant differences in accuracies and precisions obtained for each approach. The advantages and disadvantages of the two methods are discussed.

A variety of consumer products containing silver nanoparticles (Ag NPs) are currently marketed. However, their safety for humans and for the environment has not yet been established and no standard method to assess their toxicity is currently available. The objective of this work was to develop an effective method to test Ag NP toxicity and to evaluate the effects of ion release and Ag NP size on a vertebrate model. To this aim, the zebrafish animal model was exposed to a solution of commercial nanosilver. While the exposure of embryos still surrounded by the chorion did not allow a definite estimation of the toxic effects exerted by the compound, the exposure for 48 h of 3-day-old zebrafish hatched embryos afforded a reliable evaluation of the effects of Ag NPs. The effects of the exposure were detected especially at molecular level; in fact, some selected genes expressed differentially after the exposure. The Ag NP toxic performance was due to the combined effect of Ag(+) ion release and Ag NP size. However, the effect of NP size was particularly detectable at the lowest concentration of nanosilver tested (0.01 mg l(-1)) and depended on the solubilization media. The results obtained indicate that in vivo toxicity studies of nanosilver should be performed with ad hoc methods (in this case using hatched embryos) that might be different depending on the type of nanosilver. Moreover, the addition of this compound to commercial products should take into consideration the Ag NP solubilization media.

We implement relativistic BCS superconductivity in N=1 supersymmetric field theories with a U(1)_R symmetry. The simplest model contains two chiral superfields with a Kahler potential modified by quartic terms. We study the phase diagram of the gap as a function of the temperature and the specific heat. The superconducting phase transition turns out to be first order, due to the scalar contribution to the one-loop potential. By virtue of supersymmetry, the critical curves depend logarithmically with the UV cutoff, rather than quadratically as in standard BCS theory. We comment on the difficulties in having fermion condensates when the chemical potential is instead coupled to a baryonic U(1)_B current. We also discuss supersymmetric models of BCS with canonical Kahler potential constructed by "integrating-in" chiral superfields., Comment: 26 pages, 5 figures

We study new supergravity solutions related to large-$N_c$ ${\cal N}=1$ supersymmetric gauge field theories with a large number $N_f$ of massive flavors. We use a recently proposed framework based on configurations with $N_c$ color D5 branes and a distribution of $N_f$ flavor D5 branes, governed by a function $N_f S(r)$. Although the system admits many solutions, under plausible physical assumptions the relevant solution is uniquely determined for each value of $x\equiv N_f/N_c$. In the IR region, the solution smoothly approaches the deformed Maldacena-N\'u\~nez solution. In the UV region it approaches a linear dilaton solution. For $x 2$ describe a "Seiberg dual" picture where $N_f-2N_c$ flips sign.

Pulsed light technology consists of a successive repetition of short duration (325μs) and high power flashes emitted by xenon lamps. These flashlamps radiate a broadband emission light (approx. 200-1000 nm) with a considerable amount of light in the short-wave UV spectrum. In the present work, this technology was tested as a new tool for the degradation of the herbicide atrazine in water. To evaluate the presence and evolution with time of this herbicide, as well as the formation of derivatives, liquid chromatography-mass spectrometry (electrospray ionization) ion trap operating in positive mode was used. The degradation process followed first-order kinetics. Fluences about 1.8-2.3 J/cm(2) induced 50% reduction of atrazine concentration independently of its initial concentration in the range 1-1000 μg/L. Remaining concentrations of atrazine, below the current legal limit for pesticides, were achieved in a short period of time. While atrazine was degraded, no chlorinated photoproducts were formed and ten dehalogenated derivatives were detected. The molecular structures for some of these derivatives could be suggested, being hydroxyatrazine the main photoproduct identified. The different formation profiles of photoproducts suggested that the degradation pathway may include several successive and competitive steps, with subsequent degradation processes taking part from the already formed degradation products. According to the degradation efficiency, the short treatment time and the lack of chloroderivatives, this new technology could be considered as an alternative for water treatment.

7 pages, 4 figures.-- PMID: 18234487 [PubMed].-- Available online 23 Dec 2007.-- Supplementary data (2 figures) available at the paper website., A novel impedimetric immunosensor for atrazine detection has been developed. The immunosensor is based on an array of interdigitated μ-electrodes (IDμE) and immunoreagents specifically developed to detect this pesticide. Immunochemical determination of atrazine is possible without the use of any label. An atrazine-haptenized protein was covalently immobilized on the surface of the interdigitated μ-electrodes area (interdigits space) previously activated with (3-glycidoxypropyl)trimethoxysilane. Before, the gold electrodes were blocked using N-acetylcysteamine to prevent non-specific adsorptions. All biofunctionalization steps were characterized by chemical affinity methods and impedance spectroscopy. Immunosensors measures are made by exposing the sensor to solutions containing a mixture of the analyte and the specific antibody. With this configuration, the immunosensor detects atrazine with a limit of detection of 0.04 μg L−1 without the use of any label. The potential of the immunosensor to analyze pesticide residues in complex sample matrices, such as red wine, has been evaluated. The results shown that after solid-phase extraction atrazine can be determined in this type of sample with a limit of detection of 0.19 μg L−1, far below the Maximum Residue Level (MRL) established by EC for residues of this herbicide in wine., This work has been supported by the Ministry of Science and Technology (Contract numbers TEC2004-0121-E and TEC2004-06854-C03-03/MIC) and by the European Community (Food-2007-211326). The AMR group is a consolidated Grup de Recerca de la Generalitat de Catalunya and has support from the Departament d’Universitats, Recerca i Societat de la Informació de la Generalitat de Catalunya (expedient 2005SGR 00207).

The polyphenolic compositions of 31 Basque cider apple cultivars were determined in pulp, peel, and juice by high-performance liquid chromatography--diode array detection analysis of crude extracts and after thiolysis. Data sets, consisting of individual polyphenol concentrations, total procyanidin content, and the average degree of polymerization of procyanidins, were evaluated by multivariate chemometric techniques, to develop decision rules for classifying apple cultivars technologically into bitter and nonbitter categories. A preliminary study of the data structure was performed by cluster analysis and principal component analysis in each apple material. Bitter apple varieties presented higher contents of flavan-3-ols and/or dihydrochalcones than nonbitter cultivars. Different classification systems for the two categories on the basis of the chemical data were obtained applying several supervised pattern recognition procedures, such as linear discriminant analysis, K-nearest neighbors, soft independent modeling of class analogy, partial least-squares, and multilayer feed forward artificial neural networks. Excellent performance in terms of recognition and prediction abilities for both categories (100% of hits) was achieved in every case (pulp, peel, or juice). Polyphenolic profiles of apple pulp, peel, or juice provide enough information to develop classification criteria for establishing the technological group of apple cultivars (bitter or nonbitter).