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Although innate immunity is linked to metabolic health, the effect of leptin signaling in cells from the innate immune system on glucose homeostasis has not been thoroughly investigated. We generated two mouse models using Cre-lox methodology to determine the effect of myeloid cell-specific leptin receptor (Lepr) reconstitution and Lepr knockdown on in vivo glucose metabolism. Male mice with myeloid cell-specific Lepr reconstitution (Lyz2Cre+LeprloxTB/loxTB) had better glycemic control as they aged compared to male mice with whole-body transcriptional blockade of Lepr (Lyz2Cre−LeprloxTB/loxTB). In contrast, Lyz2Cre+LeprloxTB/loxTB females only had a trend for diminished hyperglycemia after a prolonged fast. During glucose tolerance tests, Lyz2Cre+LeprloxTB/loxTB males had a mildly improved plasma glucose profile compared to Cre− controls while Lyz2Cre+LeprloxTB/loxTB females had a similar glucose excursion to their Cre− controls. Myeloid cell-specific Lepr knockdown (Lyz2Cre+Leprflox/flox) did not significantly alter body weight, blood glucose, insulin sensitivity, or glucose tolerance in males or females. Expression of the cytokine interleukin 10 (anti-inflammatory) tended to be higher in adipose tissue of male Lyz2Cre+LeprloxTB/loxTB mice (p = 0.0774) while interleukin 6 (pro-inflammatory) was lower in male Lyz2Cre+Leprflox/flox mice (p Lepr in cells of myeloid lineage has beneficial effects on glucose metabolism in male mice.

The discovery of leptin was intrinsically associated with its ability to regulate body weight. However, the effects of leptin are more far-reaching and include profound glucose-lowering and anti-lipogenic effects, independent of leptin’s regulation of body weight. Regulation of glucose metabolism by leptin is mediated both centrally and via peripheral tissues and is influenced by the activation status of insulin signaling pathways. Ectopic fat accumulation is diminished by both central and peripheral leptin, an effect that is beneficial in obesity-associated disorders. The magnitude of leptin action depends upon the tissue, sex, and context being examined. Peripheral tissues that are of particular relevance include the endocrine pancreas, liver, skeletal muscle, adipose tissues, immune cells, and the cardiovascular system. As a result of its potent metabolic activity, leptin is used to control hyperglycemia in patients with lipodystrophy and is being explored as an adjunct to insulin in patients with type 1 diabetes. To fully understand the role of leptin in physiology and to maximize its therapeutic potential, the mechanisms of leptin action in these tissues needs to be further explored.

The accumulation of marine biofouling on ship hulls causes material damage, the spread of invasive species, and, indirectly, an increase in full consumption and subsequent pollutant gas emissions. Most efficient antifouling (AF) strategies rely on the conventional release of persistent, bioaccumulative, and toxic biocides incorporated in marine coatings. A simple oxygenated xanthone, 3,4-dihydroxyxanthone (1), was previously reported as a promising AF agent toward the settlement of Mytilus galloprovincialis larvae, with a therapeutic ratio higher than the commercial biocide Econea®. In this work, a structure-AF activity relationship study, an evaluation of environmental fate, and an AF efficiency in marine coatings were performed with compound 1. Hydroxy or methoxy groups at 3 and 4 positions in compound 1 favored AF activity, and groups with higher steric hindrances were detrimental. Compound 1 demonstrated low water-solubility and a short half-life in natural seawater, contrary to Econea®. In silico environmental fate predictions showed that compound 1 does not bioaccumulate in organism tissues, in contrast to other current emerging biocides, has a moderate affinity for sediments and slow migrates to ground water. No toxicity was observed against Vibrio fischeri and Phaeodactylum tricornutum. Polyurethane-based marine coatings containing compound 1 prepared through an innovative non-release-strategy were as efficient as those containing Econea® with low releases to water after 45 days. This proof-of-concept helped to establish compound 1 as a promising eco-friendly AF agent.

Biofouling, which occurs when certain marine species attach and accumulate in artificial submerged structures, represents a serious economic and environmental issue worldwide. The discovery of new non-toxic and eco-friendly antifouling systems to control or prevent biofouling is, therefore, a practical and urgent need. In this work, the antifouling activity of a series of 24 xanthones, with chemical similarities to natural products, was exploited. Nine (1, 2, 4, 6, 8, 16, 19, 21, and 23) of the tested xanthones presented highly significant anti-settlement responses at 50 μM against the settlement of mussel Mytilus galloprovincialis larvae and low toxicity to this macrofouling species. Xanthones 21 and 23 emerged as the most effective larval settlement inhibitors (EC50 = 7.28 and 3.57 µM, respectively). Additionally, xanthone 23 exhibited a therapeutic ratio (LC50/EC50) > 15, as required by the US Navy program attesting its suitability as natural antifouling agents. From the nine tested xanthones, none of the compounds were found to significantly inhibit the growth of the marine biofilm-forming bacterial strains tested. Xanthones 4, 6, 8, 16, 19, 21, and 23 were found to be non-toxic to the marine non-target species Artemia salina (21 and 23 suggest that these two compounds affected similar molecular targets and cellular processes in mussel larvae, including that related to mussel adhesion capacity. This work exposes for the first time the relevance of C-1 aminated xanthones with a 3,4-dioxygenated pattern of substitution as new non-toxic products to prevent marine biofouling.

The cherry rootstock influences the performance of the scion cultivar. It has an effect on cherry fruit quality, tree growth, yield and yield efficiency and floral and foliar nutrition. In this work, the influence of Saint Lucie 64 and Maxma 60 rootstocks on the fruit quality traits of cv. Early Bigi was evaluated. For this, several parameters, namely fruit weight (FW) and size (FS), soluble solids content (SSC), pH, titratable acidity (TA), flesh firmness (FF), epidermis rupture force (ERF), color and sensory profile, were assessed. Results showed that the fruits from trees on Saint Lucie 64 presented higher FF and ERF values and, consequently, better texture. On the other hand, fruits from trees on Maxma 60 showed sweeter cherries (higher SSC). Moreover, these trees presented the darkest cherries (lower values of L*, a*, b*, C* and hue°) and the highest SSC. Therefore, although the trees on Saint Lucie 64 produced firmer cherries, it was those with the Maxma 60 rootstock that produced sweeter and darker fruits. In conclusion, both scion–rootstock combinations proved to be good options for the region of Resende.

Sponges are important components of intertidal marine communities. There is a lack of information about intertidal marine sponge diversity in the western coast of Portugal (North-east Atlantic). In the present work we identified the most common intertidal sponges of the western coast of Portugal, and made a comprehensive list of the intertidal species described so far for this region. Sponges belonging to the Classes Calcarea and Demospongiae were identified, the former class for the first time at these locations. Demospongiae are the most common intertidal sponges, present in all sampling locations. We used an integrative approach for Demospongiae identification, using both morphological and molecular characters. Molecular identification, using a CO1 marker proved to be helpful in the identification to the genus level, despite some limitations, such as difficulty in amplification experienced for sponges as well as non-target organisms. A total of 170 specimens were collected. Seven specimens (five species) belonged to the Class Calcarea and 163 specimens (23 species) to the Class Demospongiae. The demosponge Hymeniacidon perlevis was present at all sample locations. Calcarean species were primarily found in samples taken along the south-western coast.

Summary miRNAs have crucial functions in many biological processes and are candidate biomarkers of disease. Here, we show that miR-216a is a conserved, pancreas-specific miRNA with important roles in pancreatic islet and acinar cells. Deletion of miR-216a in mice leads to a reduction in islet size, β-cell mass, and insulin levels. Single-cell RNA sequencing reveals a subpopulation of β-cells with upregulated acinar cell markers under a high-fat diet. miR-216a is induced by TGF-β signaling, and inhibition of miR-216a increases apoptosis and decreases cell proliferation in pancreatic cells. Deletion of miR-216a in the pancreatic cancer-prone mouse line KrasG12D;Ptf1aCreER reduces the propensity of pancreatic cancer precursor lesions. Notably, circulating miR-216a levels are elevated in both mice and humans with pancreatic cancer. Collectively, our study gives insights into how β-cell mass and acinar cell growth are modulated by a pancreas-specific miRNA and also suggests miR-216a as a potential biomarker for diagnosis of pancreatic diseases., Graphical abstract, Highlights miR-216a is highly abundant and enriched in mouse and human pancreas Deletion of miR-216a alters pancreatic cell cycle and DNA replication pathways miR-216a deletion decreases susceptibility to pancreatic neoplasia miR-216a levels are elevated in mice and humans with pancreatic cancer, Erener et al. identify miR-216a as a pancreas-specific miRNA affecting pancreatic pathologies. Under a high-fat diet, deletion of miR-216a reduces beta cell mass and induces acinar gene expression. In cancer-prone mice, miR-216a deletion decreases pancreatic neoplasia frequency. Circulating miR-216a levels are elevated in mice and humans with pancreatic cancer.

Pancreas is a vital organ composed of exocrine and endocrine cells that aid digestion of food and regulate blood glucose levels. Perturbations in the function of pancreatic cells leads to the development of life-burdening and/or threatening diseases such as diabetes and pancreatic cancer. Thus, it is critical to understand the molecular check-points that maintain normal pancreas physiology. MicroRNAs (miRNAs) are small non-coding RNAs involved in regulating gene expression in normal and diseased tissues. Several miRNAs have tissue-specific patterns consistent with crucial functions in many biological processes. Yet, there is limited knowledge about the role of pancreas-specific miRNAs in pancreatic pathologies. Here, we report that miR-216a is a conserved, pancreas-specific miRNA that is expressed in both endocrine and exocrine cells. Deletion of miR-216a in mice leads to reduced β-cell mass and a reduction in islet size under both chow and high-fat diet feeding conditions. We show that inhibition of miR-216a increases apoptosis and decreases cell proliferation in β- and exocrine cells.Smad7is upregulated in miR-216a deficient islets and cell cycle and proliferation are among the most significantly regulated biological processes in miR-216 knockout pancreata. Re-introduction of miR-216a in the pancreatic cancer line, PANC-1, increases cell migration more than 2-fold.In vivo, deletion of miR-216a in the pancreatic cancer prone mouse lineKrasG12D;Ptf1aCreERinhibits the propensity of pancreatic cancer precursor lesions. Our study identifies miR-216a as an important pancreas-specific miRNA which may have implications for both diabetes and pancreatic cancer.

The cyclic peptides portoamides produced by the cyanobacterium Phormidium sp. LEGE 05292 were previously isolated and their ability to condition microcommunities by allelopathic effect was described. These interesting bioactive properties are, however, still underexplored as their biotechnological applications may be vast. This study aims to investigate the antifouling potential of portoamides, given that a challenge in the search for new environmentally friendly antifouling products is to find non-toxic natural alternatives with the ability to prevent colonization of different biofouling species, from bacteria to macroinvertebrates. A multi-bioassay approach was applied to assess portoamides antifouling properties, marine ecotoxicity and molecular mode of action. Results showed high effectiveness in the prevention of mussel larvae settlement (EC50 = 3.16 &micro, M), and also bioactivity towards growth and biofilm disruption of marine biofouling bacterial strains, while not showing toxicity towards both target and non-target species. Antifouling molecular targets in mussel larvae include energy metabolism modifications (failure in proton-transporting ATPases activity), structural alterations of the gills and protein and gene regulatory mechanisms. Overall, portoamides reveal a broad-spectrum bioactivity towards diverse biofouling species, including a non-toxic and reversible effect towards mussel larvae, showing potential to be incorporated as an active ingredient in antifouling coatings.

Many methods in freshwater biomonitoring tend to be restricted to a few levels of biological organization, limiting the potential spectrum of measurable of cause-effect responses to different anthropogenic impacts. We combined distinct organisational levels, covering biological biomarkers (histopathological and biochemical reactions in liver and fish gills), community based bioindicators (fish guilds, invertebrate metrics/traits and chironomid pupal exuviae) and ecosystem functional indicators (decomposition rates) to assess ecological status at designated Water Framework Directive monitoring sites, covering a gradient of human impact across several rivers in northern Portugal. We used Random Forest to rank the variables that contributed more significantly to successfully predict the different classes of ecological status and also to provide specific cut levels to discriminate each WFD class based on reference condition. A total of 59 Biological Quality Elements and functional indicators were determined using this procedure and subsequently applied to develop the integrated Multiple Ecological Level Index (MELI Index), a potentially powerful bioassessment tool.

The reuse of the solid residues generated in the production of second-generation (2G) ethanol to obtain high-value products is a potential strategy for improving the economic and environmental viability of the overall process. This study evaluated the feasibility of using the residual solids remaining after the enzymatic hydrolysis of sugarcane bagasse for the production of cellulose nanocrystals (CNC), a valuable bionanomaterial. To this end, sugarcane bagasse subjected to steam explosion (SEB) or liquid hot water (LHWB) pretreatment was hydrolysed using different loadings of a commercial cellulase cocktail. Samples of SEB and LHWB were hydrolysed enzymatically, resulting in glucose releases close to 40 g/L, which would be suitable for producing 2G ethanol by microbial fermentation. The solid residues after the enzymatic hydrolysis step presented cellulose contents of up to 54 %, indicating that a significant amount of recalcitrant crystalline cellulose remained available for subsequent use. These solid residues were purified and submitted to acid hydrolysis, resulting in the successful formation of CNC with crystallinity close to 80 %, lengths of 193–246 nm and diameters of 14–18 nm. The CNC produced presented morphology, dimensions, physical-chemical characteristics, thermal stability and crystallinity within the ranges reported for this type of material. Moreover, the enzyme loading or the type of hydrothermal pretreatment process employed here showed no significant effects on the CNC obtained, indicating that these variables could be flexibly adjusted according to specific interests.

Fruit cracking is one of the main concerns in sweet cherry production and is caused by a heavy rainfall before and during the harvest. This physiological disorder leads to severe economic losses, which can be more or less effective depending on the cracked region of the fruit: in the cheeks (side cracks), in the stylar scar region, or in the stem cavity region. Sweet cherry cracking can be affected by several factors such as cultivar, growing conditions, rootstock, fruit size, flesh osmotic potential, cuticular characteristics of the skin, and stage of fruit development. In this sense, the objective of this work was to evaluate the cracking incidence in two sweet cherry cultivars (Early Bigi and Lapins grafted on &ldquo, Saint Lucie 64&rdquo, rootstock) and correlate the cracking index with other quality parameters. Fruits were harvested on 2 May (cv. Early Bigi) and on 27 May (cv. Lapins) 2019 at their commercial ripening stage. In the field, the total yield and the trunk cross-sectional area were determined for each tree in order to calculate the yield efficiency. In the laboratory, the cracking index was determined in 150 fruits without visual defects. In addition, fruit size and weight, wax content, flesh firmness, epidermis rupture force, total soluble solids, pH, titratable acidity, and maturity index of 30 fruits were also evaluated. In general, all the analyzed quality parameters were influenced by the cultivar, being that cv. Lapins presented larger, heavier, firmer, and sweeter fruits, with more acidity and higher maturation index. However, cv. Lapins also presented higher cracking index, which was positively correlated with all the parameters above-mentioned and negatively correlated with the wax content. In fact, cv. Early Bigi presented a high wax content and simultaneously a low cracking index. The stylar scar region cracks were the most prevalent in both cultivars. These results allowed us to conclude that, in the North Portugal region, the Lapins cherries presented better quality attributes than the Early Bigi cherries. However, the latter are still very valuable to the region due to its early ripening. Additionally, it was also possible to conclude that bigger, firmer, more mature, and with lower wax content cherries were more sensitive to cracking than the smaller fruits, soft-fleshed, less mature, and with higher wax content.

Publisher's version (útgefin grein)., Marine sponges and cyanobacteria have a long history of co-evolution, with documented genome adaptations in cyanobionts. Both organisms are known to produce a wide variety of natural compounds, with only scarce information about novel natural compounds produced by cyanobionts. In the present study, we aimed to address their toxicological potential, isolating cyanobacteria (n = 12) from different sponge species from the coast of Portugal (mainland, Azores, and Madeira Islands). After large-scale growth, we obtained both organic and aqueous extracts to perform a series of ecologically-relevant bioassays. In the acute toxicity assay, using nauplii of Artemia salina, only organic extracts showed lethality, especially in picocyanobacterial strains. In the bioassay with Paracentrotus lividus, both organic and aqueous extracts produced embryogenic toxicity (respectively 58% and 36%), pointing to the presence of compounds that interfere with growth factors on cells. No development of pluteus larvae was observed for the organic extract of the strain Chroococcales 6MA13ti, indicating the presence of compounds that affect skeleton formation. In the hemolytic assay, none of the extracts induced red blood cells lysis. Organic extracts, especially from picoplanktonic strains, proved to be the most promising for future bioassay-guided fractionation and compounds isolation. This approach allows us to classify the compounds extracted from the cyanobacteria into effect categories and bioactivity profiles., Funding: This work was financed by UID/Multi/04423/2013 and by the Structured Program of R&D&I INNOVMAR—Innovation and Sustainability in the Management and Exploitation of Marine Resources (reference NORTE-01-0145-FEDER-000035, Research Line NOVELMAR), funded by the Northern Regional Operational Program (NORTE2020) through the European Regional Development Fund (ERDF).and by the grants PTDC/MAR/099642/2008, PhD grants SFRH/BD/73033/2010 and the Fellowship grant BI/PTDC/MAR/099642/2008/2011-030.

Research report Free PMC Article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6226392/ Introduction: Combined oxidative phosphorylation deficiency 20 (COXPD20) is a mitochondrial respiratory chain complex (RC) disorder, caused by disease-causing variants in the VARS2 gene, which encodes a mitochondrial aminoacyl-tRNA synthetase. Here we describe a patient with fatal mitochondrial encephalopathy caused by a homozygous VARS2 gene missense variant. Case Report: We report the case of a girl, the first child of non-consanguineous and healthy parents, born from an uneventful term pregnancy, who presented, in the neonatal period, major hypotonia and microcephaly. At 4 months of age she showed poor eye contact, nystagmus, global psychomotor development delay and failure to thrive, without dysmorphic features. Focal seizures started at 24 months which evolved to a severe epileptic encephalopathy and finally to super refractory status epilepticus, leading to her death at 28 months of age. Etiologic investigation encompassing metabolic and genetic causes failed to disclose a diagnosis. Post-mortem exome sequencing allowed the identification of a pathogenic variant in VARS2 gene in the homozygous state (c.1100C > T, p.Thr367Ile) in the patient, inherited from her heterozygous parents, leading to the diagnosis of COXPD2. Conclusion: To the best of our knowledge, this is the fifth case described in the literature of a child with disease-causing variant in VARS2. With this report we expand the knowledge about the phenotype associated with this very rare mitochondrial defect, further emphasizing the use of exome sequencing as a very powerful diagnostic tool. info:eu-repo/semantics/publishedVersion

Objective Free fatty acids (FFAs) cause insulin resistance and are often elevated in obesity. Chronic ingestion of diets rich in saturated fat induces more insulin resistance than diets rich in unsaturated fat, however, it remains unclear whether different FFAs cause distinct levels of insulin resistance in the short-term, which is relevant to the feeding and fasting cycle. Protein kinase C (PKC)-δ is implicated in hepatic insulin resistance. Therefore, we investigated the effects of short-term elevation of fatty acids with different degrees of unsaturation on hepatic insulin action and liver PKC-δ membrane translocation, a marker of activation. Materials/Methods Triglyceride emulsions of Soybean Oil + Heparin (polyunsaturated (POLY)), Olive Oil + Heparin (monounsaturated (MONO)), Lard Oil + Heparin (saturated (SATU)), or saline (SAL) were infused intravenously for 7 h to elevate plasma FFA concentrations ~ 3–4 fold in rats. During the last 2 h of infusion, a hyperinsulinemic–euglycemic clamp with tritiated glucose methodology was performed to examine hepatic and peripheral insulin sensitivity. Results Surprisingly, SATU, MONO, and POLY impaired peripheral insulin sensitivity (glucose utilization divided by insulin) to a similar extent. Furthermore, all lipids induced a similar degree of hepatic insulin resistance compared to SAL. Although there were changes in hepatic content of lipid metabolites, there were no significant differences in liver PKC-δ membrane translocation across fat groups. Conclusions In summary, in the short-term, FFAs with different degrees of unsaturation impair peripheral insulin sensitivity and induce hepatic insulin resistance as well as hepatic PKC-δ translocation to the same extent.

The efficient use of renewable lignocellulosic feedstocks to obtain biofuels and other bioproducts is a key requirement for a sustainable biobased economy. This requires novel and effective strategies to reduce the cost contribution of the cellulolytic enzymatic cocktails needed to convert the carbohydrates into simple sugars, in order to make large-scale commercial processes economically competitive. Here, we propose the use of the whole solid-state fermentation (SSF) medium of mixed filamentous fungi as an integrated one-pot strategy for on-site enzyme production, biomass hydrolysis, and ethanol production. Ten different individual and mixed cultivations of commonly used industrial filamentous fungi (Aspergillus niger, Aspergillus oryzae, Trichoderma harzianum, and Trichoderma reesei) were performed under SSF and the whole media (without the extraction step) were used in the hydrolysis of pretreated sugarcane bagasse. The cocultivation of T. reesei with A. oryzae increased the amount of glucose released by around 50%, compared with individual cultivations. The release of glucose and reducing sugars achieved using the whole SSF medium was around 3-fold higher than obtained with the enzyme extract. The addition of soybean protein (0.5% w/w) during the hydrolysis reaction further significantly improved the saccharification performance by blocking the lignin and avoiding unproductive adsorption of enzymes. The results of the alcoholic fermentation validated the overall integrated process, with a volumetric ethanol productivity of 4.77 g/L.h, representing 83.5% of the theoretical yield. These findings demonstrate the feasibility of the proposed one-pot integrated strategy using the whole SSF medium of mixed filamentous fungi for on-site enzymes production, biomass hydrolysis, and ethanol production. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:671-680, 2018.

Fat-induced hepatic insulin resistance plays a key role in the pathogenesis of type 2 diabetes in obese individuals. Although PKC and inflammatory pathways have been implicated in fat-induced hepatic insulin resistance, the sequence of events leading to impaired insulin signaling is unknown. We used Wistar rats to investigate whether PKCδ and oxidative stress play causal roles in this process and whether this occurs via IKKβ- and JNK-dependent pathways. Rats received a 7-h infusion of Intralipid plus heparin (IH) to elevate circulating free fatty acids (FFA). During the last 2 h of the infusion, a hyperinsulinemic-euglycemic clamp with tracer was performed to assess hepatic and peripheral insulin sensitivity. An antioxidant, N-acetyl-l-cysteine (NAC), prevented IH-induced hepatic insulin resistance in parallel with prevention of decreased IκBα content, increased JNK phosphorylation (markers of IKKβ and JNK activation, respectively), increased serine phosphorylation of IRS-1 and IRS-2, and impaired insulin signaling in the liver without affecting IH-induced hepatic PKCδ activation. Furthermore, an antisense oligonucleotide against PKCδ prevented IH-induced phosphorylation of p47phox(marker of NADPH oxidase activation) and hepatic insulin resistance. Apocynin, an NADPH oxidase inhibitor, prevented IH-induced hepatic and peripheral insulin resistance similarly to NAC. These results demonstrate that PKCδ, NADPH oxidase, and oxidative stress play a causal role in FFA-induced hepatic insulin resistance in vivo and suggest that the pathway of FFA-induced hepatic insulin resistance is FFA → PKCδ → NADPH oxidase and oxidative stress → IKKβ/JNK → impaired hepatic insulin signaling.

The use of improved biofertilisers such as rhizobia and arbuscular mycorrhizal fungi (AMF) in legume crops is a promising technology that can be an alternative source of nitrogen and phosphorus. A common problem when growing faba bean (Vicia faba L.) and other leguminous plants is the low efficiency of native rhizobial strains. Consequently, there is a need to search for efficient nitrogen-fixing inoculant strains able to increase crop productivity. This study aimed to test the effects of single and dual inoculation with Rhizobium laguerreae and AMF on the growth and yield of faba bean plants. Several parameters were evaluated at flowering stage (number of flowers, stems and leaves, shoot and root biomass, leaf area, leaf mass per area and leaf area ratio, and gas-exchange parameters) and at harvesting stage (number and weight of pods and seeds). Plants receiving single inoculation with Rhizobium laguerreae showed a significant increase in number of leaves, leaf area, leaf mass per area and leaf area ratio, as well as in all yield parameters. Single inoculation with AMF also significantly increased the yield parameters of faba bean plants. Co-inoculation presented significant improvements in leaf area ratio and in all productivity parameters compared with the control, but co-inoculation was not significantly different from the individual inoculations.

The Northwestern Portuguese region is densely populated and highly industrialized, suffering from high anthropogenic pressure. To assess the biological effect of the several pollutants that are constantly released to the water, a biomarker-based biomonitoring is a promising approach that may provide early-warning signals of pollutants exposure. Fish gill is the first target of pollutants action, thus histopathological and biochemical changes may constitute potential biomarkers. To evaluate this hypothesis, three native fish species (barbel—Luciobarbus bocagei, chub—Squalius carolitertii and nase—Pseudochondrostoma sp.) were sampled in Northwestern Portuguese rivers, the gill histopathological changes were qualitative and quantitatively analyzed and the lipid peroxidation and glutathione-S-transferase activity were determined. A multivariate statistical analysis was performed to establish correlations between these biological responses, environmental variables and ecological status. The quantitative evaluation of the main histopathological changes and oxidative stress responses emphasize the differences, among species, in the responses to the presence of contaminants in water. Discriminant canonical analysis showed that filament epithelium proliferation, necrosis and GST activity were the main contributors to discriminate the ecological status classification. In addition, the results showed that a wide range of environmental factors are influencing fish physiology. In conclusion, the gill biological responses, although not reflecting specific contaminants, can be used as biomarkers of ecosystems perturbation.

We have shown in rats that sodium salicylate (SS), which inhibits IkBa kinase B (IKKB), prevents hepatic and peripheral insulin resistance caused by short-term (7 h) i.v. administration of Intralipid and heparin (IH). We wished to further determine whether this beneficial effect of SS persisted after prolonged (48 h) IH infusion, which better mimics the chronic free fatty acid (FFA) elevation of obesity. Hence, we performed hyperinsulinemic euglycemic clamps with tritiated glucose methodology to determine hepatic and peripheral insulin sensitivity in rats infused with saline, IH, IH and SS, or SS alone. SS prevented peripheral insulin resistance (P

This study investigated the role of silicon (Si) and manganese (Mn) rates on the activity of peroxidases (POX), polyphenoloxidases (PPO) and phenylalanine ammonia-lyases (PAL) on rice plants non-inoculated and inoculated with Bipolaris orzyae. Rice plants (cultivar Metica 1) were grown in nutrient solution with 0 (-Si) or 2 mmol Si L-1 (+Si) and with 0.5, 2.5 and 10 μmol Mn L-1. Plants were inoculated with B. oryzae and leaf samples were collected at 6, 12, 18, 24, 36 and 48 h after inoculation (hai). Leaf samples were also collected from non-inoculated plants at these same time-points. POX activity increased for -Si plants inoculated with B. oryzae at both rates of 0.5 and 2.5 µmol Mn L-1 with one peak at 48 hai at 10 µmol Mn L-1. For plants supplied with Si, POX activity also increased, but seemed to be low at the rates of 2.5 and 10 µmol Mn L-1. POX activity did not show to be greatly influenced by the Mn rates in the presence of Si. However, in the absence of Si, POX activity increased. PPO activity on -Si plants increased at the rate of 0.5 µmol Mn L-1 and was not affected by the other two Mn rates, except a peak at 18 hai at the rate of 10 µmol Mn L-1. In the presence of Si, PPO activity increased on plants supplied with 2.5 µmol Mn L-1 in contrast to the other two Mn rates for which the PPO activity decreased. By comparing the -Si and +Si treatments at the rate of 2.5 µmol Mn L-1, PPO activity increased from 18 to 36 hai in the presence of Si than on its absence. PAL activity on -Si plants decreased regardless of the Mn rates. On plants supplied with Si and inoculated with B. oryzae, PAL showed low activity at the highest Mn rate and also at the rate of 0.5 µmol Mn L-1, besides its activity been very low compared to the non-inoculated plants. PAL did not increase in activity in the presence of Si, but on its absence, high levels of activity were achieved. Results from this study showed that the activities of POX, PPO and PAL were not boosted by Si at any Mn rate.

Spot blotch, caused by the fungus Bipolaris sorokiniana, is one of the most important diseases on wheat. The effects of silicon (Si) on this wheat disease were studied. Plants of wheat cultivars BR-18 and BRS-208 were grown in plastic pots containing Si-deficient soil amended with either calcium silicate (+Si) or calcium carbonate (−Si). The content of Si in leaf tissue was significantly increased by 90.5% for the +Si treatment. There was no significant difference between Si treatments for calcium content, so variations in Si accounted for differences in the level of resistance to spot blotch. The incubation period was significantly increased by 40% for the +Si treatment. The area under spot blotch progress curve, number of lesions per cm2 of leaf area, and real disease severity significantly decreased by 62, 36 and 43.5% in +Si treatment. There was no significant effect of Si on lesion size. The role played by total soluble phenolics in the increased resistance to spot blotch of plants from both cultivars supplied with Si was not clear. Plants from cultivar BR-18 supplied with Si showed the highest values for concentration of lignin-thioglycolic acid derivatives during the most advanced stages of fungus infection. Chitinase activity was high at the most advanced stages of fungus infection on leaves from both cultivars supplied with Si and may have had an effect on fungus growth based on the reduction of the components of resistance evaluated. Peroxidase activity was found to be high only at 96 h after inoculation of both cultivars supplied with Si. Polyphenoloxidase activity had no apparent effect on resistance regardless of Si treatments. Results revealed that supplying Si to wheat plants can increase resistance against spot blotch.

Leaf streak, caused by Xanthomonas translucens pv. undulosa, is the major bacterial disease of wheat in Brazil and other countries worldwide. This study aimed to evaluate the effect of silicon (Si) on disease development and the biochemical mechanisms possibly involved in resistance potentialized by this element. Plants of cv. BR-18, susceptible to leaf streak, were grown in plastic pots containing Si-deficient soil amended with either calcium silicate (+Si) or calcium carbonate (−Si). The content of Si increased (P ≤ 0.05) by 96.5% for the +Si when compared with −Si treatment. There was no difference (P ≥ 0.05) between Si treatments for calcium content on leaf tissue, so variations in Si accounted for differences in the level of resistance to leaf streak. There was no difference (P ≥ 0.05) between Si treatments for incubation period, latent period, necrotic leaf area, and severity estimated by the software quant. However, chlorotic leaf area was reduced (P ≤ 0.05) by 50.2% for the +Si when compared with −Si treatment. There was no difference (P ≥ 0.05) between Si treatments for the bacteria population on leaf tissue; however, the values seemed to be somewhat lower in the +Si treatment from 4 to 8 days after inoculation (d.a.i.) on leaves from plants supplied with Si. There was no difference (P ≥ 0.05) between Si treatments for electrolyte leakage. The concentration of total soluble phenolics and lignin-thioglycolic acid (LTGA) derivatives did not show any apparent signs of increase during the course of infection and seemed to be slightly higher on plants not supplied with Si at the most advanced stages of bacterial infection. Chitinase activity was high at the most advanced stages of bacterial infection on leaves from +Si treatment and probably affected bacterial growth on leaf tissue. Peroxidase activity following bacterial infection was not increased by Si, but can be linked with the highest concentration of LTGA derivatives at 12 d.a.i. of plants supplied with Si. Polyphenoloxidase activity did not affect wheat resistance to leaf streak regarding of the Si treatments. The results clearly suggest that supplying Si to wheat plants can increase resistance to leaf streak possibly through an increase in tissue lignification and the participation of chitinases and peroxidases.

OBJECTIVE—We previously demonstrated that 1) obesity impairs and 2) sex influences insulin sensitivity of protein metabolism, while 3) poor glycemic control in type 2 diabetes accelerates protein turnover in daily fed-fasted states. We hypothesized that type 2 diabetes alters the insulin sensitivity of protein metabolism and that sex modulates it. RESEARCH DESIGN AND METHODS—Hyperinsulinemic (∼570 pmol/l), euglycemic (5.5 mmol/l), and isoaminoacidemic (kept at postabsorptive concentrations) clamps were performed in 17 hyperglycemic type 2 diabetic subjects and 23 subjects without diabetes matched for age and body composition, after 7 days on a inpatient, protein-controlled, isoenergetic diet. Glucose and leucine kinetics were determined using tracers. RESULTS—In type 2 diabetes, postabsorptive (baseline) glycemia was 8–9 mmol/l, glucose production (Ra) and disposal (Rd) were elevated, and once clamped, endogenous glucose Ra remained greater and Rd was less (P < 0.05) than in control subjects. Baseline leucine kinetics did not differ despite higher insulin levels. The latter was an independent predictor of leucine flux within each sex. With clamp, total flux increased less (P = 0.016) in type 2 diabetic men, although protein breakdown decreased equally (∼20%) in male groups but less in female groups. Whereas protein synthesis increased in male control subjects and in both female groups, it did not in male subjects with type 2 diabetes. In men, homeostasis model assessment of insulin resistance predicted 44%, and, in women, waist-to-hip ratio predicted 40% of the change in synthesis. CONCLUSIONS—During our clamp, men with type 2 diabetes have greater insulin resistance of protein metabolism than that conferred by excess adiposity itself, whereas women do not. These results may have implications for dietary protein requirements.

Elevated levels of plasma free fatty acids (FFA), which are commonly found in obesity, induce insulin resistance. FFA activate protein kinases including the proinflammatory IκBα kinase β (IKKβ), leading to serine phosphorylation of insulin receptor substrate 1 (IRS-1) and impaired insulin signaling. To test whether resveratrol, a polyphenol found in red wine, prevents FFA-induced insulin resistance, we used a hyperinsulinemic-euglycemic clamp with a tracer to assess hepatic and peripheral insulin sensitivity in overnight-fasted Wistar rats infused for 7 h with saline, Intralipid plus 20 U·mL−1 heparin (IH; triglyceride emulsion that elevates FFA levels in vivo; 5.5 μL·min−1) with or without resveratrol (3 mg·kg−1·h−1), or resveratrol alone. Infusion of IH significantly decreased glucose infusion rate (GIR; P < 0.05) and peripheral glucose utilization (P < 0.05) and increased endogenous glucose production (EGP; P < 0.05) during the clamp compared with saline infusion. Resveratrol co-infusion, however, completely prevented the effects induced by IH infusion: it prevented the decreases in GIR (P < 0.05 vs. IH), peripheral glucose utilization (P < 0.05 vs. IH), and insulin-induced suppression of EGP (P < 0.05 vs. IH). Resveratrol alone had no effect. Furthermore, IH infusion increased serine (307) phosphorylation of IRS-1 in soleus muscle (∼30-fold, P < 0.001), decreased total IRS-1 levels, and decreased IκBα content, consistent with activation of IKKβ. Importantly, all of these effects were abolished by resveratrol (P < 0.05 vs. IH). These results suggest that resveratrol prevents FFA-induced hepatic and peripheral insulin resistance and, therefore, may help mitigate the health consequences of obesity.

Cowpea (Vigna unguiculata (L.) Walp.), a plant broadly cultivated for human consumption and animal feed, is among the most nutritious grain legumes. Most of the areas where cowpea is grown are drought-prone, and there is a need to address this issue, with water scarcity becoming a major concern in agriculture. Cowpea is known to form mutualistic associations with nitrogen-fixing (NF) bacteria and arbuscular mycorrhizal (AM) fungi. These beneficial soil microorganisms have the capacity to benefit plants by reducing the effects of environmental stresses, including drought. Our aim was to study the effect of inoculation with Bradyrhizobium elkanii and Rhizophagus irregularis on the growth and grain yield of cowpea under water-deficit conditions. Under moderate water deficit, grain yield was increased by 63%, 55% and 84% in plants inoculated with B. elkanii, R. irregularis and B. elkanii + R. irregularis, respectively. Under severe water deficit, inoculation with B. elkanii and B. elkanii + R. irregularis resulted in grain-yield enhancement of 45% and 42%, respectively. The use of cowpea inoculated with NF bacteria and AM fungi has great potential for sustainable agricultural production under drought conditions.

Glycogen synthesis is a major component of the insulin response, and defective glycogen synthesis is a major portion of insulin resistance. Insulin regulates glycogen synthase (GS) through incompletely defined pathways that activate the enzyme through dephosphorylation and, more potently, allosteric activation. We identify Epm2aip1 as a GS-associated protein. We show that the absence of Epm2aip1 in mice impairs allosteric activation of GS by glucose 6-phosphate, decreases hepatic glycogen synthesis, increases liver fat, causes hepatic insulin resistance, and protects against age-related obesity. Our work identifies a novel GS-associated GS activity-modulating component of insulin resistance.

The mechanisms whereby prolonged plasma free fatty acids elevation, as found in obesity, causes hepatic insulin resistance are not fully clarified. We herein investigated whether inhibition of p38 mitogen-activated protein kinase (MAPK) prevented hepatic insulin resistance following prolonged lipid infusion. Chronically cannulated rats were subdivided into one of four intravenous (i.v.) treatments that lasted 48 h: Saline (5.5 μl min−1), Intralipid plus heparin (IH, 20% Intralipid+20 U ml−1 heparin; 5.5 μl min−1), IH+p38 MAPK inhibitor (SB239063) and SB239063 alone. During the last 2 h of treatment, a hyperinsulinemic (5 mU kg−1 min−1) euglycemic clamp together with [3-3H] glucose methodology was carried out to distinguish hepatic from peripheral insulin sensitivity. We found that SB239063 prevented IH-induced hepatic insulin resistance, but not peripheral insulin resistance. SB239063 also prevented IH-induced phosphorylation of activating transcription factor 2 (ATF2), a marker of p38 MAPK activity, in the liver. Moreover, in another lipid infusion model in mice, SB239063 prevented hepatic but not peripheral insulin resistance caused by 48 h combined ethyloleate plus ethylpalmitate infusion. Our results suggest that inhibition of p38 MAPK may be a useful strategy in alleviating hepatic insulin resistance in obesity-associated disorders.

OBJECTIVE Insulin resistance associates with chronic inflammation, and participatory elements of the immune system are emerging. We hypothesized that bacterial elements acting on distinct intracellular pattern recognition receptors of the innate immune system, such as bacterial peptidoglycan (PGN) acting on nucleotide oligomerization domain (NOD) proteins, contribute to insulin resistance. RESEARCH DESIGN AND METHODS Metabolic and inflammatory properties were assessed in wild-type (WT) and NOD1/2−/− double knockout mice fed a high-fat diet (HFD) for 16 weeks. Insulin resistance was measured by hyperinsulinemic euglycemic clamps in mice injected with mimetics of meso-diaminopimelic acid–containing PGN or the minimal bioactive PGN motif, which activate NOD1 and NOD2, respectively. Systemic and tissue-specific inflammation was assessed using enzyme-linked immunosorbent assays in NOD ligand–injected mice. Cytokine secretion, glucose uptake, and insulin signaling were assessed in adipocytes and primary hepatocytes exposed to NOD ligands in vitro. RESULTS NOD1/2−/− mice were protected from HFD-induced inflammation, lipid accumulation, and peripheral insulin intolerance. Conversely, direct activation of NOD1 protein caused insulin resistance. NOD1 ligands induced peripheral and hepatic insulin resistance within 6 h in WT, but not NOD1−/−, mice. NOD2 ligands only modestly reduced peripheral glucose disposal. NOD1 ligand elicited minor changes in circulating proinflammatory mediators, yet caused adipose tissue inflammation and insulin resistance of muscle AS160 and liver FOXO1. Ex vivo, NOD1 ligand caused proinflammatory cytokine secretion and impaired insulin-stimulated glucose uptake directly in adipocytes. NOD1 ligand also caused inflammation and insulin resistance directly in primary hepatocytes from WT, but not NOD1−/−, mice. CONCLUSIONS We identify NOD proteins as innate immune components that are involved in diet-induced inflammation and insulin intolerance. Acute activation of NOD proteins by mimetics of bacterial PGNs causes whole-body insulin resistance, bolstering the concept that innate immune responses to distinctive bacterial cues directly lead to insulin resistance. Hence, NOD1 is a plausible, new link between innate immunity and metabolism.

The discovery of insulin nearly a century ago revolutionized the treatment of diabetes mellitus, particularly type 1 diabetes mellitus (T1DM), and initiated extensive research into the effects of insulin. At approximately the same time, it was shown that patients with cancer were characterized by glucose intolerance and impaired insulin sensitivity of glucose metabolism has been subsequently found in cancer [1, 2]. Insulin, a peptide hormone produced by the β cells in the pancreas, is anabolic, as it stimulates synthesis of glycogen, protein, and triglycerides and it suppresses glucose production by the body, while stimulating glucose uptake from the circulation [3]. Moreover, insulin action is tissue-specific, since it depends on the binding of insulin to its cell-surface receptor. The insulin receptor, which is composed of two transmembrane β chains and two extracellular α chains, has intrinsic tyrosine kinase activity [4, 5] and binding of insulin to its receptor initiates a signaling cascade characterized by phosphorylation events and genomic effects. The insulin receptor is expressed in various tissues, including the most widely studied insulin sensitive tissues, namely liver, skeletal muscle, adipose tissue, and selective regions of the brain. Insulin has mitogenic effects [6], but the ensuing discussion will highlight the metabolic actions of insulin. Furthermore, although insulin regulates the metabolism of all three macronutrients [7], which is interlinked, the focus will be on insulin’s effect on carbohydrate metabolism.

This study investigated how a defect in the active uptake of silicon (Si) affects rice resistance to brown spot. Plants from a rice mutant (low silicon 1 [lsi1]) and its wild-type counterpart (cv. Oochikara), growing in hydroponic culture with (+Si; 2 mM) or without (–Si) Si, were inoculated with Bipolaris oryzae. Si concentration in leaf tissue of cv. Oochikara and the lsi1 mutant increased by 381 and 263%, respectively, for the +Si treatment compared with the –Si treatment. The incubation period was 6 h longer in the presence of Si. The area under brown spot progress curve for plants from cv. Oochikara and the lsi1 mutant was reduced 81 and 50%, respectively, in the presence of Si. The reduced number of brown epidermal cells on leaves from cv. Oochikara and the lsi1 mutant supplied with Si contributed to the lower lipid peroxidation and electrolyte leakage. The concentration of total soluble phenolics in cv. Oochikara supplied with Si (values of 4.2 to 15.4 μg g–1 fresh weight) was greater compared with plants not supplied with Si (values of 1.9 to 11.5 μg g–1 fresh weight). The concentration of lignin was also important to the resistance of cv. Oochikara and the lsi1 mutant. Polyphenoloxidase activity did not contribute to the resistance of cv. Oochikara and the lsi1 mutant to brown spot, regardless of Si supply. Peroxidase and chitinase activities were higher in cv. Oochikara and the lsi1 mutant supplied with Si. These results bring novel evidence of the involvement of Si in a more complex defense mechanism than simply the formation of a physical barrier to avoid or delay fungal penetration.

A principal medida de controle da ferrugem do cafeeiro, causada por Hemileia vastatrix, é o uso de fungicidas. O fornecimento de silício (Si) às plantas é uma estratégia de controle interessante considerando o potencial desse elemento em aumentar a resistência de várias espécies de plantas à patógenos. Este trabalho avaliou o efeito da aplicação foliar do Si na redução da severidade da ferrugem e na possível potencialização da atividade de seis enzimas relacionadas com a resistência de plantas à patógenos. Mudas de café (cultivar Catuaí Vermelho 44) foram pulverizadas com água destilada, solução de silicato de potássio (KSi) (35 g/L, pH 10,5), KSi (35 g/L, pH 5,5) e solução de acibenzolar-S-metil (ASM) (200 µg/L) 24 horas antes da inoculação. Não houve diferença significativa entre os tratamentos para os teores foliares de Si e potássio. A severidade foi significativamente maior em mudas pulverizadas com água em relação aos demais tratamentos. O ASM reduziu significativamente a severidade em 70% em relação à aplicação de água. A aplicação de soluções de KSi, independente do pH, também reduziu a severidade. O ASM foi eficiente em aumentar a atividade de quitinases e β-1,3-glucanases, porém a aplicação de KSi, independente do pH da solução, foi ineficiente em potencializar a atividade das seis enzimas estudadas, embora tenha reduzido a severidade. The major method for control of coffee leaf rust, caused by Hemileia vastatrix, is the use of fungicides. The supply of silicon (Si) to plants is an interesting control strategy because this element can increase the resistance of many plant species to pathogens. This study aimed to evaluate the effect of foliar application of Si on reducing rust severity as well as to determine if it can potentiate the activity of enzymes related to host resistance to pathogens. Coffee plants (cultivar Catuaí Vermelho 44) were sprayed with distilled water, potassium silicate (KSi) solution (35 g/L, pH 10.5), KSi (35 g/L, pH 5.5), and acibenzolar-S-methyl (ASM) solution (200 µg/L) 24 hours before inoculation. There was no significant difference among the treatments regarding the content of Si and potassium in the leaf tissue. Rust severity was significantly higher on plants sprayed with water as compared to the other treatments. The ASM significantly decreased rust severity by 70% in comparison to the water spray treatment. Foliar application of KSi, regardless of the pH, was efficient in decreasing rust severity. The ASM was efficient in increasing the activity of chitinases and β-1,3-glucanases. On the other hand, the application of KSi, regardless of the pH, was inefficient to potentiate the activity of these six enzymes studied, even though it had a great impact on reducing rust severity.

Relatedness among parents, variation in clonal fertility and background pollination deviate the realized genetic gain and the gene diversity of open pollinated seed orchard from expectation, in particular in wind pollinated species such as Pinus pinaster Aiton. This work investigates the genetic variation, the mating system and the pollen contamination in a P. pinaster clonal seed orchard (CSO), by screening the 60 clones from the CSO and the seeds collected from 21 mother-trees with three nuclear microsatellites. The expected diversity was similar, but the observed heterozygosity decreased 20% in the progenies compared with the parental trees. The outcrossing rate was 90.1%, the biparental inbreeding 21.7% computed through a multilocus approach, and the observed selfing 3.9%. The observed gene flow from outside the CSO was 52.4%. From the results we concluded that the observed gene flow and the biparental inbreeding were high, and care should be taken in the implementation and management of future CSO, in particular clones should be checked for relatedness and the ramet number could be directly proportional to their breeding value., L'apparentement entre parents, la variation de fertilité entre clones et la pollution pollinique font dévier le gain génétique réalisé et la diversité génétique des valeurs attendues en verger à graines de clones à pollinisation libre, en particulier pour une espèce à pollinisation anémophile comme Pinus pinaster Aiton. Ce travail étudie la variation génétique, le système de reproduction et la contamination du pollen d'un verger à graines de clones (VGC) de P. pinaster, en génotypant les 60 clones du VGC et les graines récoltées sur 21 arbres-mères pour trois marqueurs microsatellites nucléaires. La diversité attendue s'est révélée similaire mais l'hétérozygotie observée a diminué de 20 % chez les descendants par rapport aux parents. Le taux d'allofécondation était de 90,1 %, la consanguinité biparentale calculée grâce à une approche multilocus était de 21,7 % et le taux d'autofécondation observé était de 52,4 %. D'après ces résultats, nous avons conclu que les flux de gènes observés et la consanguinité biparentale étaient élevés et que des précautions devaient être prises dans la mise en place et la gestion de futurs VGC, l'apparentement entre clones devrait en particulier être vérifié et le nombre de copies d'un individu pourrait être directement proportionnel à sa valeur génétique.