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Polyphenols in human nutrition: from the in vitro antioxidant capacity to the beneficial effects on cardiometabolic health and related inter-individual variability - an overview and perspective
No full textOxidative damage of cells and tissues is broadly implicated in human pathophysiology, including cardiometabolic diseases. Polyphenols, as important constituents of human diet and potent in vitro free radical scavengers, have been extensively studied for their beneficial effects on cardiometabolic health. However, it has been demonstrated that the in vivo antioxidant activity of polyphenols is distinct from their in vitro free radical scavenging capacity. Indeed, bioavailability of nutritional polyphenols is low, and conditioned by complex mechanisms of absorption, distribution, metabolism and excretion. Nowadays it is commonly accepted that the cellular antioxidant activity of polyphenols is mainly carried out via modification of transcription of genes involved in antioxidant defense. Importantly, polyphenols contribute to the cardiometabolic health also by modulation of plethora of cellular processes that are not directly associated with antioxidant enzymes, through nutri(epi)genomic mechanisms. Numerous human intervention studies have demonstrated beneficial effects of polyphenols on the key cardiometabolic risk factors. However, inconsistency of the results of some studies led to identification of the inter-individual variability in response to consumption of polyphenols. In perspective, a detailed investigation of the determinants of this inter-individual variability will potentially lead us towards personalized dietary recommendations. The phenomenon of inter-individual variability is also of relevance for supplementation with antioxidant (pro)vitamins
Endothelin increases the proliferation of rat olfactory mucosa cells
No full textThe olfactory mucosa holds olfactory sensory neurons directly in contact with an aggressive environment. In order to maintain its integrity, it is one of the few neural zones which are continuously renewed during the whole animal life. Among several factors regulating this renewal, endothelin acts as an anti-apoptotic factor in the rat olfactory epithelium. In the present study, we explored whether endothelin could also act as a proliferative factor. Using primary culture of the olfactory mucosa, we found that an early treatment with endothelin increased its growth. Consistently, a treatment with a mixture of BQ(123) and BQ(788) (endothelin receptor antagonists) decreased the primary culture growth without affecting the cellular death level. We then used combined approaches of calcium imaging, reverse transcriptase-quantitative polymerase chain reaction and protein level measurements to show that endothelin was locally synthetized by the primary culture until it reached confluency. Furthermore, in vivo intranasal instillation of endothelin receptor antagonists led to a decrease of olfactory mucosa cell expressing proliferating cell nuclear antigen (PCNA), a marker of proliferation. Only short-term treatment reduced the PCNA level in the olfactory mucosa cells. When the treatment was prolonged, the PCNA level was not statistically affected but the expression level of endothelin was increased. Overall, our results show that endothelin plays a proliferative role in the olfactory mucosa and that its level is dynamically regulated
Absolute quantitation of microbes using 16S rRNA gene metabarcoding: A rapid normalization of relative abundances by quantitative PCR targeting a 16S rRNA gene spike‐in standard
No full textMetabarcoding of the 16S rRNA gene is commonly used to characterize microbial communities, by estimating the relative abundance of microbes. Here, we present a method to retrieve the concentrations of the 16S rRNA gene per gram of any environmental sample using a synthetic standard in minuscule amounts (100 ppm to 1% of the 16S rRNA sequences) that is added to the sample before DNA extraction and quantified by two quantitative polymerase chain reaction (qPCR) reactions. This allows normalizing by the initial microbial density, taking into account the DNA recovery yield. We quantified the internal standard and the total load of 16S rRNA genes by qPCR. The qPCR for the latter uses the exact same primers as those used for Illumina sequencing of the V3‐V4 hypervariable regions of the 16S rRNA gene to increase accuracy. We are able to calculate the absolute concentration of the species per gram of sample, taking into account the DNA recovery yield. This is crucial for an accurate estimate as the yield varied between 40% and 84%. This method avoids sacrificing a high proportion of the sequencing effort to quantify the internal standard. If sacrificing a part of the sequencing effort to the internal standard is acceptable, we however recommend that the internal standard accounts for 30% of the environmental 16S rRNA genes to avoid the PCR bias associated with rare phylotypes. The method proposed here was tested on a feces sample but can be applied more broadly on any environmental sample. This method offers a real improvement of metabarcoding of microbial communities since it makes the method quantitative with limited efforts
Does a positive density perception increase the probability of living in the ideal housing type? Evidence from the Loire-Atlantique Département in France.
No full textWhat does the ideal housing type look like? A 2015 online survey of individuals living in the Loire-Atlantique Département in France provided 1,134 interviews, which we analyze using a mixed-effect probit model. We look at the probability of living in the ideal housing type related to 28 variables of dwelling and respondent characteristics, density perception, district perception, type of municipality, and proximity to education, healthcare and food facilities. The issue is important because certain housing types yield greater land consumption and longer trips. Local governments support infill developments with higher built-up density levels to conserve land and support walking, cycling, and transit. We find that the probability of living in the ideal housing type has no relationship to density perception. What matters is a positive district perception and proximity to healthcare. Well-designed infill development with higher built-up density levels can succeed, associating a higher probability of living in the ideal housing type with suitable urban forms given the physical constraints of territories, in a sustainable development framework.Qu’est-ce qu’un habitat idéal ? A partir d’une enquête en ligne réalisée en 2015 auprès de 1134 individus résidant dans le département de Loire-Atlantique (France), nous analysons les déterminants individuels influençant la probabilité de considérer son habitat comme idéal. Nous examinons cette probabilité à partir de 28 variables décrivant le logement et les caractéristiques des répondants. A partir d’un modèle probit à effets mixtes, nous prenons en compte la perception du quartier, la proximité des commerces alimentaires et des établissements d'enseignement et de santé ainsi que le type de territoire de résidence (urbain, périurbain, rural) et la densité perçue par les répondants de leur habitat. L'enjeu est important puisque certains types d’habitat sont à l’origine de consommations foncières plus élevées et de déplacements plus longs pour les ménages. Afin de mieux préserver les espaces naturels et agricoles et d’encourager les modes de déplacement alternatifs à la voiture individuelle (marche, vélo, transport collectif, etc.), les collectivités locales soutiennent des opérations d’aménagement à forte densité bâtie. Nous révélons que la probabilité de considérer que l’on vit dans le type d’habitat idéal est sans rapport avec la densité perçue. Ce qui importe, c'est une perception du quartier positive et la proximité des services de santé. Bien pensées, des opérations d’aménagement à forte densité bâtie peuvent donc permettre la conciliation d’un habitat considéré comme idéal par ses résidents avec le respect de formes urbaines compatibles avec les contraintes morphologiques des territoires, dans un contexte de développement durable
Green assets of equines in the european context of the ecological transition of agriculture
No full textEquines have a peculiar place in our society. From livestock to sport, through to landscape managers and leisure partners, equines show a wide range of little-known environmental advantages and assets. Today’s wake-up calls about the environment are progressively putting pressure on stakeholders of the agricultural sector, including the equine industry. This study focusses on the main environmental consequences of equine use and possession in Europe based on scientific and technical sources under the lens of five leading sectors where equines show unique impacts as green assets. Now, more than ever before, it is important to highlight the role of equines as a green alternative in political debates and management practices to give them the place equines deserve in the ecological transition of agriculture
Flavescence Dorée Phytoplasma Has Multiple ftsH Genes that Are Differentially Expressed in Plants and Insects
No full textFlavescence dorée (FD) is a severe epidemic disease of grapevines caused by FD phytoplasma (FDP) transmitted by the leafhopper vector Scaphoideus titanus. The recent sequencing of the 647-kbp FDP genome highlighted an unusual number of genes encoding ATP-dependent zinc proteases FtsH, which have been linked to variations in the virulence of "Candidatus Phytoplasma mali" strains. The aims of the present study were to predict the FtsH repertoire of FDP, to predict the functional domains and topologies of the encoded proteins in the phytoplasma membrane and to measure the expression profiles in different hosts. Eight complete ftsH genes have been identified in the FDP genome. In addition to ftsH6, which appeared to be the original bacterial ortholog, the other seven gene copies were clustered on a common distinct phylogenetic branch, suggesting intra-genome duplication of ftsH. The expression of these proteins, quantified in plants and insect vectors in natural and experimental pathosystems, appeared to be modulated in a host-dependent manner. Two of the eight FtsH C-tails were predicted by Phobius software to be extracellular and, therefore, in direct contact with the host cellular content. As phytoplasmas cannot synthesize amino acids, our data raised questions regarding the involvement of FtsH in the adaptation to hosts via potentially enhanced recycling of phytoplasma cellular proteins and host protein degradation
Examples of current research on indicators of adaptative response in periparturient dairy ruminants : Adipose tissue in livestock
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BRCAness, SLFN11, and RB1 loss predict response to topoisomerase I inhibitors in triple-negative breast cancers
No full textINPUT OF DEEP PHENOTYPING IN THE METABOLIC SYNDROME STRATIFICATION
No full textIntroduction
Metabolic syndrome (MetS), defined as a cluster of cardiometabolic factors, is a public health challenge because of its growing prevalence. In the context of personalized medicine, new tools are necessary to bring additional knowledge about MetS etiology, better stratify populations and customise strategies for prevention. The objective of this study was to characterize the MetS phenotypic spectrum using complementary untargeted metabolomics platforms (HRMS, RMN).
Technological and methodological innovation
A case-control study was designed within the Quebec NuAge cohort1. Six complementary untargeted
metabolomic/lipidomic approaches were performed on serum samples collected at recruitment and 3 years later. Procedures were set up to guaranty the inter-laboratory standardisation from sample preparation to data processing, performed using reproducible online Galaxy workflows. A full feature selection strategy was developed to build a comprehensive molecular MetS signature, stable over time.
Results and impact
A wide range of metabolites (lipids, carbohydrates, amino-acids, peptides…) reflecting subject stability and providing new insights about underlying mechanisms, were found to be modulated. An optimized reduced signature was proposed, allowing good prediction performances (12% misclassification, AUC=0.95, CI:[0.92-0.98]). These results demonstrated the interest of a multidimensional molecular phenotyping as part of the next generation of medicine tools in the frame of noncommunicable diseases.
References
[1] Gaudreau P et al., 2007. Rejuvenation Res.10(3):377-386