Deficient selenium status of a healthy adult Spanish population.

INTRODUCTION Selenium is an essential micronutrient for human health, being a cofactor for enzymes with antioxidant activity that protect the organism from oxidative damage. An inadequate intake of this mineral has been associated with the onset and progression of chronic diseases such as hypertension, diabetes, coronary diseases, asthma, and cancer. For this reason, knowledge of the plasma and erythrocyte selenium levels of a population makes a relevant contribution to assessment of its nutritional status. OBJECTIVE The objective of the present study was to determine the nutritional status of selenium and risk of selenium deficiency in a healthy adult population in Spain by examining food and nutrient intake and analyzing biochemical parameters related to selenium metabolism, including plasma and erythrocyte levels and selenium-dependent glutathione peroxidase (GPx) enzymatic activity. MATERIAL AND METHODS We studied 84 healthy adults (31 males and 53 females) from the province of Granada, determining their plasma and erythrocyte selenium concentrations and the association of these levels with the enzymatic activity of glutathione peroxidase (GPx) and with life style factors. We also gathered data on their food and nutrient intake and the results of biochemical analyses. Correlations were studied among all of these variables. RESULTS The mean plasma selenium concentration was 76.6 ± 17.3 μg/L (87.3 ± 17.4 μg/L in males, 67.3 ± 10.7 μg/L in females), whereas the mean erythrocyte selenium concentration was 104.6 μg/L (107.9 ± 26.1 μg/L in males and 101.7 ± 21.7 μg/L in females). The nutritional status of selenium was defined by the plasma concentration required to reach maximum GPx activity, establishing 90 μg/L as reference value. According to this criterion, 50% of the men and 53% of the women were selenium deficient. CONCLUSIONS Selenium is subjected to multiple regulation mechanisms. Erythrocyte selenium is a good marker of longer term selenium status, while plasma selenium appears to be a marker of short-term nutritional status. The present findings indicate a positive correlation between plasma selenium concentration and the practice of physical activity. Bioavailability studies are required to establish appropriate reference levels of this mineral for the Spanish population.

Characterisation of "fou2", a constitutive wound-activated mutant and analysis of the proteome and leaf physiology in the region proximal to wounds in Arabidopsis

Résumé : Les jasmonates (JA), une famille d'hor1none végétale, jouent un rôle central dans la réponse à la blessure, et aux attaques d'insectes et de pathogènes. Les JA sont principalement dérivés d'un acide gras, l'acide linolénique. L'addition par une lipoxygénase d'une molécule d'oxygène à l'acide linolénique initie la synthèse de JA. Cependant les mécanismes régulant l'activation de la biosynthèse de JA ne sont pas encore connus. C'est pour cette raison que dans ce travail, nous avons caractérisé chez Arabidopsis thaliana (l'Arabette des Dames) un mutant fou2 dont l'activité lipoxygénase est plus élevée que celle d'une plante sauvage. Les niveaux de JA sont constitutivement plus élevés et l'activation de la synthèse de JA après blessure est fortement plus induite chez fou2 que chez le type sauvage. En outre, fou2 est plus résistant au pathogène Botrytis cinerea et à la chenille Spodoptera littoralis. Afin de comprendre quel mécanisme chez fou2 génére ce phénotype, nous avons cloné le gène responsable du phénotype de fou2. Le mutant fou2 porte une mutation dans le gène d'un canal à deux pores transportant probablement du potassium, du lumen de la vacuole végétale vers le compartiment cytosolique. L'analyse du protéome de fou2 a permis d'identifier une expression plus élevée de sept protéines régulées par les JA ou le stress. La découverte de l'implication d'un canal dans le phénotype de fou2 renforce l'hypothèse que les flux de cations pourraient être impliqués dans les étapes précoces de la synthèse des JA. Nous avons également étudié le protéome et la physiologie d'une feuille blessée, Pour évaluer les changements d'expression protéique en réponse à la blessure et contrôlés par les JA, nous avons quantifié l'expression de 5937 protéines chez une plante d'Arabidopsis sauvage et chez un mutant incapable de synthétiser des JA. Parmi ces 5937 protéines, nous avons identifié 99 protéines régulées par la blessure chez le type sauvage. Nous avons observé pour 65% des protéines dont l'expression protéique changeait après blessure une bonne corrélation entre la quantité de transcrits et de protéines. Plusieurs enzymes de la voie des chorismates impliquées dans la biosynthèse des acides aminés phénoliques étaient induites par les JA après blessure. Une quantification des acides aminés a montré que les niveaux d'acides aminés phénoliques augmentaient significativement après blessure. La blessure induisait aussi des changements dans l'expression de protéines impliquées dans la réponse au stress et particulièrement au stress oxydatif. Nous avons quantifié l'état réduit et oxydé du glutathion, un tripeptide qui, sous sa forme réduite, est l'antioxydant majeur des cellules. Nous avons trouvé une quantité significativement plus élevée de glutathion oxydé chez le type sauvage blessé que chez la plante aus blessée. Ce résultat suggère que la génération d'un stress oxydatif et la proportion relative de glutathions réduits et oxydés sont contrôlés par les JA après blessure. Abstract : Plants possess a family of potent fatty acid-derived wound-response and developmental regulators: the jasmonates. These compounds are derived from the tri?unsaturated fatty acid a-linolenic-acid (18:3). Addition of an oxygen molecule to 18:3 by 13-lipoxygenases (13-LOX) initiates JA biosynthesis. Actually components regulating the activation of JA biosynthesis are poorly defined. Therefore we characterized in Arabidopsis thaliana the fatty acid Qxygenation upregulated 2 (fou2) mutant, which was previously isolated in a screen for mutants with an enhanced 13-LOX activity. As a consequence of this increased 13-LOX activity, JA levels in fou2 are higher than in wild type (WT) and wounding strongly increased JA biosynthesis compared to WT. fou2 was more resistant to the fungus Botrytis cinerea and the generalist caterpillar Spodaptera littomlis, The fou2 mutant carries a missense mutation in the Two Pore Channel 1 gene (TPCJ), which encodes a vacuolar cation channel transporting probably K* into the cytosol. Patchclamp analysis of fou2 vacuolar membranes showed faster time-dependent conductivity and activation of the mutated channel at lower membrane potentials than wild-type. Proteomic analysis of fou2 leaves identified increased levels of seven biotic stress- and JA- inducible proteins. The discovery of the implication of a channel in the fou2 phenotype strenghtens the hypothesis that cation fluxes might be implicated in early steps of JA synthesis. We further concentrated on the proteome and leaf physiology in the region proximal to wounds in Arabidopsis using the WT and the aos JA-biosynthesis deficient mutant in order to find JA- induced proteins changes. We used two successive proteomic methods to assess protein changes in response to wounding Arabidopsis leaves, two dimensional electrophoresis (2DE) and linear trap quadrupole ion-trap mass spectrometry. In total 5937 proteins were quantified. We identified 99 wound-regulated proteins in the WT. Most these proteins were also wound-regulated at the transcript level showing a good correlation between transcript and protein abundance. We identified several wound-regulated enzymes involved in amino acid biosynthesis and confirmed this result by amino acid quantification. Proteins involved in stress reponses were upregulated, particularly in redox species regulation. We found a significantly higher quantity of oxidized glutathione in wounded WT relative to wounded aos leaves. This result suggests that levels of reduced glutathione are controlled by JA after wounding.

Toxicological and biochemical analysis of the susceptibility of sylvatic Triatoma infestans from the Andean Valley of Bolivia to organophosphate insecticide

To increase our knowledge of the natural susceptibility of Triatoma infestans to an organophosphate insecticide, we performed toxicological and biochemical studies on three sylvatic populations from Bolivia and two populations from domestic dwellings from Bolivia and Argentina. Fifty-per-cent lethal doses (LD50) were determined based on the topical application of fenitrothion on first instar nymphs and mortality was assessed at 24 h. Both type of populations exhibited LD50ratios significantly higher than 1 with a range of the values (1.42-2.47); the maximum value were found in a sylvatic (-S) population, Veinte de Octubre-S. Samples were biochemically analysed using a glutathione S-transferase activity assay. The highest significant activity was obtained for Veinte de Octubre-S and the lowest activity was obtained for the reference population (102.69 and 54.23 pmol per minute per mg of protein respectively). Two out of the three sylvatic populations (Veinte de Octubre-S and Kirus Mayu-S) exhibited significantly higher glutathione S-transferase activity than that of the reference population. Based on this analysis of the natural susceptibility of this organism to organophosphate insecticides, continental and focal surveys of organophosphate susceptibility should be conducted to evaluate the evolution and distribution of this phenomenon.

WNK3 abrogates the NEDD4-2-mediated inhibition of the renal Na+-Cl- cotransporter.

The serine/threonine kinase WNK3 and the ubiquitin-protein ligase NEDD4-2 are key regulators of the thiazide-sensitive Na+-Cl- cotransporter (NCC), WNK3 as an activator and NEDD2-4 as an inhibitor. Nedd4-2 was identified as an interacting partner of WNK3 through a glutathione-S-transferase pull-down assay using the N-terminal domain of WNK3, combined with LC-MS/MS analysis. This was validated by coimmunoprecipitation of WNK3 and NEDD4-2 expressed in HEK293 cells. Our data also revealed that the interaction between Nedd4-2 and WNK3 does not involve the PY-like motif found in WNK3. The level of WNK3 ubiquitylation did not change when NEDD4-2 was expressed in HEK293 cells. Moreover, in contrast to SGK1, WNK3 did not phosphorylate NEDD4-2 on S222 or S328. Coimmunoprecipitation assays showed that WNK3 does not regulate the interaction between NCC and NEDD4-2. Interestingly, in Xenopus laevis oocytes, WNK3 was able to recover the SGK1-resistant NEDD4-2 S222A/S328A-mediated inhibition of NCC and further activate NCC. Furthermore, elimination of the SPAK binding site in the kinase domain of WNK3 (WNK3-F242A, which lacks the capacity to bind the serine/threonine kinase SPAK) prevented the WNK3 NCC-activating effect, but not the Nedd4-2-inhibitory effect. Together, these results suggest that a novel role for WNK3 on NCC expression at the plasma membrane, an effect apparently independent of the SPAK kinase and the aldosterone-SGK1 pathway.

Public health impact of statin prescribing strategies based on jupiter

Texte intégral: http://www.springerlink.com/content/3q68180337551r47/fulltext.pdf

Blood pressure loci identified with a gene-centric array.

Raised blood pressure (BP) is a major risk factor for cardiovascular disease. Previous studies have identified 47 distinct genetic variants robustly associated with BP, but collectively these explain only a few percent of the heritability for BP phenotypes. To find additional BP loci, we used a bespoke gene-centric array to genotype an independent discovery sample of 25,118 individuals that combined hypertensive case-control and general population samples. We followed up four SNPs associated with BP at our p < 8.56 × 10(-7) study-specific significance threshold and six suggestively associated SNPs in a further 59,349 individuals. We identified and replicated a SNP at LSP1/TNNT3, a SNP at MTHFR-NPPB independent (r(2) = 0.33) of previous reports, and replicated SNPs at AGT and ATP2B1 reported previously. An analysis of combined discovery and follow-up data identified SNPs significantly associated with BP at p < 8.56 × 10(-7) at four further loci (NPR3, HFE, NOS3, and SOX6). The high number of discoveries made with modest genotyping effort can be attributed to using a large-scale yet targeted genotyping array and to the development of a weighting scheme that maximized power when meta-analyzing results from samples ascertained with extreme phenotypes, in combination with results from nonascertained or population samples. Chromatin immunoprecipitation and transcript expression data highlight potential gene regulatory mechanisms at the MTHFR and NOS3 loci. These results provide candidates for further study to help dissect mechanisms affecting BP and highlight the utility of studying SNPs and samples that are independent of those studied previously even when the sample size is smaller than that in previous studies.

Effect of a specific supplement enriched with n-3 polyunsaturated fatty acids on markers of inflammation, oxidative stress and metabolic status of ear, nose and throat cancer patients.

Malnutrition affects 40-50% of patients with ear, nose and throat (ENT) cancer. The aim of this study was to assess changes induced by a specific nutritional supplement enriched with n-3 polyunsaturated fatty acids, fiber and greater amounts of proteins and electrolytes, as compared with a standard nutritional supplement, on markers of inflammation, oxidative stress and metabolic status of ENT cancer patients undergoing radiotherapy (RT). Fourteen days after starting RT, 26 patients were randomly allocated to one of two groups, 13 supplemented with Prosure, an oncologic formula enriched with n-3 polyunsaturated fatty acids, fiber and greater amounts of proteins and electrolytes (specific supplement), and 13 supplemented with Standard-Isosource (standard supplement). Patients were evaluated before RT, and 14, 28 and 90 days after starting RT. The results showed that there were no significant differences between the groups, but greater changes were observed in the standard supplement group, such as a decline in body mass index (BMI), reductions in hematocrit, erythrocyte, eosinophil and albumin levels, and a rise in creatinine and urea levels. We concluded that metabolic, inflammatory and oxidative stress parameters were altered during RT, and began to normalize at the end of the study. Patients supplemented with Prosure showed an earlier normalization of these parameters, with more favorable changes in oxidative stress markers and a more balanced evolution, although the difference was not significant.

Unanswered clinical questions in the management of cardiometabolic risk in the elderly: a statement of the Spanish society of internal medicine.

BACKGROUND Despite the progressive increase in life expectancy and the relationship between aging with multi-morbidities and the increased use of healthcare resources, current clinical practice guidelines (CPG) on cardiometabolic risk cannot be adequately applied to elderly subjects with multiple chronic conditions. Its management frequently becomes complicated by both, an excessive use of medications that may lead to overtreatment, drug interactions and increased toxicity, and errors in dosage and non-compliance. Concerned by this gap, the Spanish Society of Internal Medicine created a group of independent experts on cardiometabolic risk who discussed what they considered to be unanswered questions in the management of elderly patients. DISCUSSION Current guidelines do not specifically address the problem of elderly with multiple chronic conditions. For this reason, the combined use of the limited available evidence, clinical experience and common sense, could all help us to address this unmet need. In very old people, life expectancy and functionality are the most important factors for guiding potential treatments. Their higher propensity to develop serious adverse events and their shorter lifespan could prevent them from obtaining the potential benefits of the interventions administered. SUMMARY In this document, experts on cardiometabolic risk factors have established a number of consensual recommendations that have taken into account international guidelines and clinical experience, and have also considered the more effective use of healthcare resources. This document is intended to provide general recommendations for clinicians and to promote the effective use of procedures and medications.

Long-term effects of varying consumption of ω3 fatty acids in ear, nose and throat cancer patients: assessment 1 year after radiotherapy.

Abstract A prospective 1-year follow-up study in ear, nose, and throat (ENT) cancer patients was carried out one year after radiotherapy to assess the effect of varying consumption of ω3 fatty acid according to whether they consumed more or less than the 50th percentile of ω3 fatty acids. Clinical, analytical, inflammatory (CRP and IL-6), and oxidative variables (TAC, GPx, GST, and SOD) were evaluated. The study comprised 31 patients (87.1% men), with a mean age of 61.3 ± 9.1 years. Hematological variables showed significant differences in the patients with a lower consumption of ω3 fatty acids. A lower mortality and longer survival were found in the group with ω3 fatty acid consumption ≥50th percentile but the differences were not significant. No significant difference was reached in toxicity, inflammation, and oxidative stress markers. The group with ω3 fatty acid consumption <50th percentile significantly experienced more hematological and immune changes.

Faut-il traiter les dyslipidémies chez les personnes âgées et très âgées. [Should we treat dyslipidemia in the elderly and the oldest old?].

Therapy of dyslipidemia in the elderly and the oldest old remains controversial. Several studies have shown benefits of statins on secondary prevention of cardiovascular disease in older adults up to 80 years, but data remain scarce after that age. Fewer studies have assessed the impact of statins in primary prevention in the elderly. Most studies have not included adults older than 75 years, and absolute risk reduction is far lower compared to secondary prevention. Use of statins for primary prevention in this age group should be based on individual decision, taking into account patient's functional and cognitive status, comorbidities and other therapies to avoid drugs interactions, with the help of shared-decision making.

First insights into the transcriptome and development of new genomic tools of a widespread circum-Mediterranean tree species, Pinus halepensis Mill.

Aleppo pine (Pinus halepensis Mill.) is a relevant conifer species for studying adaptive responses to drought and fire regimes in the Mediterranean region. In this study, we performed Illumina next-generation sequencing of two phenotypically divergent Aleppo pine accessions with the aims of (i) characterizing the transcriptome through Illumina RNA-Seq on trees phenotypically divergent for adaptive traits linked to fire adaptation and drought, (ii) performing a functional annotation of the assembled transcriptome, (iii) identifying genes with accelerated evolutionary rates, (iv) studying the expression levels of the annotated genes and (v) developing gene-based markers for population genomic and association genetic studies. The assembled transcriptome consisted of 48,629 contigs and covered about 54.6 Mbp. The comparison of Aleppo pine transcripts to Picea sitchensis protein-coding sequences resulted in the detection of 34,014 SNPs across species, with a Ka /Ks average value of 0.216, suggesting that the majority of the assembled genes are under negative selection. Several genes were differentially expressed across the two pine accessions with contrasted phenotypes, including a glutathione-s-transferase, a cellulose synthase and a cobra-like protein. A large number of new markers (3334 amplifiable SSRs and 28,236 SNPs) have been identified which should facilitate future population genomics and association genetics in this species. A 384-SNP Oligo Pool Assay for genotyping with the Illumina VeraCode technology has been designed which showed an high overall SNP conversion rate (76.6%). Our results showed that Illumina next-generation sequencing is a valuable technology to obtain an extensive overview on whole transcriptomes of nonmodel species with large genomes.

Lupus erythematosus and other autoimmune diseases related to statin therapy: a systematic review.

BACKGROUND: Statins have been increasingly associated with drug-induced autoimmune reactions, including lupus erythematosus. OBJECTIVE: To identify and determine the clinical and biological characteristics of statin-induced autoimmune reactions. MATERIAL AND METHODS: The MEDLINE database (1966 to September 2005) was used to identify all reported cases of statin-induced autoimmune diseases. The keywords used were statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, adverse effects, autoimmune disease, lupus erythematosus, dermatomyositis and polymyositis. RESULTS: Twenty-eight cases of statin-induced autoimmune diseases have been published so far. Systemic lupus erythematosus was reported in 10 cases, subacute cutaneous lupus erythematosus in three cases, dermatomyositis and polymyositis in 14 cases and lichen planus pemphigoides in one case. Autoimmune hepatitis was observed in two patients with systemic lupus erythematosus. The mean time of exposure before disease onset was 12.8+/-18 months; range 1 month-6 years. Systemic immunosuppressive therapy was required in the majority of cases. In many patients, antinuclear antibodies were still positive many months after clinical recovery. A lethal outcome has been recorded in two patients despite aggressive immunosuppressive therapy. CONCLUSION: Long-term exposure to statins may be associated with drug-induced lupus erythematosus and other autoimmune disorders. Fatal cases have been reported despite early drug discontinuation and aggressive systemic immunosuppressive therapy.

Alloimmunity and nonimmunologic risk factors in cardiac allograft vasculopathy.

Graft vasculopathy is an accelerated form of coronary artery disease that occurs in transplanted hearts. Despite major advances in immunosuppression, the prevalence of the disease has remained substantially unchanged during the last two decades. According to the 'response to injury' paradigm, graft vasculopathy is the result of a continuous inflammatory response to tissue injury initiated by both alloantigen-dependent and independent stress responses. Experimental evidence suggests that these responses may become self-sustaining, as allograft re-transplantation into the donor strain at a later stage fails to prevent disease progression. Histological evidence of endothelitis and arteritis, in association with intima fibrosis and atherosclerosis, reflects the central role of alloimmunity and inflammation in the development of arterial lesions. Experimental results in gene-targeted mouse models indicate that cellular and humoral immune responses are both involved in the pathogenesis of graft vasculopathy. Circulating antibodies against donor endothelium are found in a significant number of patients, but their pathogenic role is still controversial. Alloantigen-independent factors include donor-transmitted coronary artery disease, surgical trauma, ischaemia-reperfusion injury, viral infections, hyperlipidaemia, hypertension, and glucose intolerance. Recent therapeutic advances include the use of novel immunosuppressive agents such as sirolimus (rapamycin), HMG-CoA reductase inhibitors, calcium channel blockers, and angiotensin converting enzyme inhibitors. Optimal treatment of cardiovascular risk factors remains of paramount importance.