Endothelin increases the proliferation of rat olfactory mucosa cells

The 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

Milk metabolites as noninvasive indicators of nutritional status of mid-lactation Holstein and Montbéliarde cows

The objective was to investigate the effects of feed restriction on concentrations of selected milk metabolites in midlactation Holstein and Montbéliarde cows, and explore their correlations with energy balance and classic plasma and milk indicators of nutritional status. Eight Holstein and 10 Montbéliarde cows (165 ± 21 DIM) underwent 6 d of feed restriction during which feed allowance was reduced to meet 50% of their net energy for lactation (NEL) requirements. The experiment was divided in four periods: Control (CONT; d -3 to -1), restriction (REST; d 1 to 6), WEEK1 (d 7 to 13) and WEEK2 (d 14 to 18) after refeeding at ad libitum intake. Intake, milk production, energy balance and plasma metabolites were used to validate the feed restriction model. Concentrations of seven milk metabolites, i.e. BHB, glucose, glucose-6-phosphate, isocitrate, glutamate, uric acid and free amino groups were measured in morning milk samples, and fatty acids in pooled PM and AM samples. Feed restriction induced a negative energy balance (-42.5 ± 4.4 MJ/d), increased plasma non-esterified fatty acids and BHB, and decreased plasma glucose concentrations. Feed restriction increased milk glucose-6-phosphate and isocitrate (+38% and +39%, respectively) and decreased milk BHB, glucose, glutamate, uric acid and free amino group concentrations (-20%, -57%, -65%, -42% and -14%, respectively), compared to pre- restriction. Milk concentrations of medium chain fatty acids (e.g. sum of C10 to C15) decreased and those of long chain (e.g. 18:0, cis-9 18:1) increased during restriction. Breed differences were not detected for the majority of variables. All studied milk metabolites were significantly correlated with energy balance (rs = 0.48, 0.63, -0.31, -0.45, 0.61 for BHB, glucose, glucose-6-phosphate, isocitrate and glutamate, respectively). Milk glucose and glutamate were the most correlated with plasma metabolites and milk FA associated with lipomobilization. These results suggest that milk metabolites may be used as noninvasive indicators of NEB and metabolic status of dairy cows

Data from a proteomic analysis highlight different osmoadaptations in two strain of Propionibacterium freudenreichii

The article presents a proteomic data set generated by a comparative analysis of the proteomes of Propionibacterium freudenreichii, comparing the CIRM-BIA 129 and CIRM-BIA 1025 strains. The two strains were cultivated until the beginning of the stationary phase in a chemical defined medium (MMO), and in this medium in the presence of NaCl, with or without glycine betaine. Whole-cell proteins were extracted, trypsinolyzed and analyzed by nano LC-MS/MS, prior to identification and classification by function using the X!Tandem pipeline software and the proteomic data from NCBI.nlm.nigh.gov. Quantification of proteins was then carried out in order to detect change in their expression depending on the culture medium. This article is related to the research article entitled “Benefits and drawbacks of osmotic adjustment in Propionibacterium freudenreichii”. The comparative proteomic analysis of the two strains reveal strain-dependent and medium-dependent stress proteomes in the probiotic P. freudenreichii

Mass balance and long-term soil accumulation of trace elements in arable crop systems amended with urban composts or cattle manure during 17 years

Organic waste products (OWP) application to crop lands makes possible nutrients recycling. However, it can result in long-term accumulation of trace elements (TE) in soils. The present study aimed at (i) assessing the impact of regular applications of urban composts and manure on the TE contents of topsoils and crops in a long-term field experiment, (ii) comparing the TE mass balances with the stock variations of TE in soils, and (iii) proposing a prospective evaluation of this practice, based on estimated soil safe threshold values and simulations of soil TE accumulation for 100 years. In the long-term field experiment, physico-chemical properties and TE contents (Cd, Cr, Cu, Hg, Ni, Pb and Zn) have been measured in OWP, soils, plants and leaching waters for the period 1998–2015, and used for mass balance calculations and long-term simulations of TE accumulations. The composts of green wastes and sludge (GWS) and of municipal solid waste (MSW) were the OWP with the largest TE contents, while the farmyard manure tended to have the lowest. Repeated application of OWP led to significant accumulation of Zn and Cu in the topsoil layer (not for Cr, Cd, Hg, Ni, Pb), especially with GWS, without overpassing calculated protective threshold values. No effect of repeated application of OWP has been observed on TE contents in grains (wheat, maize, barley). The positive mass balance has been dominated by the input flux of TE through OWP and resulted in the observed increases of soil stocks for Cu and Zn. Prospective simulation of soil content evolution until 2100 showed that soil content reached 0.4 mg Cd kg−1 soil (GWS, MSW), 38 mg Cu kg−1 soil (GWS) and 109 mg Zn kg−1 soil (GWS), which remained lower than protective threshold values

Comparative transcriptomics enables the identification of functional orthologous genes involved in early leaf growth.

Leaf growth is a complex trait for which many similarities exist in different plant species, suggesting functional conservation of the underlying pathways. However, a global view of orthologous genes involved in leaf growth showing conserved expression in dicots and monocots is currently missing. Here we present a genome-wide comparative transcriptomics analysis between Arabidopsis and maize, identifying conserved biological processes and gene functions active during leaf growth. Despite the orthology complexity between these distantly related plants, 926 orthologous gene groups including 2,829 Arabidopsis and 2,974 maize genes with similar expression during leaf growth were found, indicating conservation of the underlying molecular networks. We found 65% of these genes involved in one-to-one orthology, whereas only 28.7% of the groups with divergent expression had one-to-one orthology. Within the pool of genes with conserved expression, 19 transcription factor families were identified, demonstrating expression conservation of regulators active during leaf growth. Additionally, 25 Arabidopsis and 25 maize putative targets of the TCP TFs with conserved expression were determined based on the presence of enriched transcription factor binding sites. Based on large-scale phenotypic data, we observed that genes with conserved expression have a higher probability to be involved in leaf growth and that leaf-related phenotypes are more frequently present for genes having orthologs between dicots and monocots than clade-specific genes. This study shows the power of integrating transcriptomics with orthology data to identify or select candidates for functional studies during leaf development in flowering plants

INPUT OF DEEP PHENOTYPING IN THE METABOLIC SYNDROME STRATIFICATION

Introduction 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

Permanent grassland classifications predict agronomic and environmental characteristics well, but not ecological characteristics

Permanent grasslands produce highly diverse ecosystem goods and services, which need to be easily assessed by decision makers. Naturalists and agronomists classify grasslands in different ways to predict ecological, agronomic and environmental characteristics of the grasslands. However, few studies have compared the prediction abilities of these different classifications using the same botanical releves, and none has explored the utility of combining classifications. In this study, we attributed a grassland class from each of three classifications (phytosociological, agronomic and functional) to 250 permanent grasslands in north-eastern France to predict 16 characteristics: nine ecological, three agronomic and four environmental. We used statistical model selection to identify the classification or combination of classifications that best predicted each characteristic. Our results showed great prediction ability of agronomic classification, which created the best models for predicting agronomic (yield) and environmental (management, elevation) characteristics. We also identified a strong prediction ability of combining two or all three classifications to predict seven other grassland characteristics. However, grassland classifications did not predict most of the ecological characteristics well. We can assume that phytosociological classification, despite its mainstream use, predicts grassland characteristics less well than agronomic classification. We recommend combining grassland classifications to improve rapid prediction abilities. This study provides new knowledge useful for developing grassland classifications which meet the needs of agronomists and naturalists

Valorisation des protéines par maîtrise des fonctionnalités

La naturalité des produits alimentaires représente une demande forte des consommateurs des pays développés. La naturalité s’entend comme une réduction de l’emploi des additifs pour la fabrication, le stockage, la distribution ou l’usage des produits alimentaires, mais aussi la préservation des propriétés organoleptique et santé des macro- et micronutriments constitutifs. Les protéines sont des constituants essentiels pour texturer des aliments. Il existe cependant 2 limites à l’utilisation des protéines pour leurs propriétés de texture : une trop faible concentration en protéines ne permet pas de texturer une matrice alimentaire de façon satisfaisante, tandis qu’une trop forte concentration en protéines thermo-sensibles, comme les protéines de lactosérum, conduit à une agrégation excessive ou une gélification pendant leur traitement thermique. Un recours à l’addition d’agents gélifiants ou stabilisants est donc nécessaire pour atteindre la texture souhaitée (solide, visqueuse, fluide). Dans le cadre d’un projet interrégional, Profil, nous avons étudié le rôle de différentes fractions protéiques du lait pour contrôler la texture des émulsions sur une large gamme de concentration en protéines de lactosérum et sans ajout d’additif en combinant les propriétés de stabilité thermique des assemblages de protéines de lactosérum et les propriétés interfaciales des caséines. A teneur faible en protéines, notamment en caséines, les assemblages de protéines de lactosérum s’adsorbent à l’interface et connectent les globules gras, ce qui permet de texturer l’émulsion. A plus forte concentration en caséines, celles-ci couvrent l’interface au détriment des assemblages de protéines de lactosérum qui restent dans la phase dispersée et les émulsions sont fluides et stables après traitement thermique, même à forte concentration en protéines. Ces travaux ouvrent une voie innovante pour la création de produits laitiers sans additif répondant à la demande de naturalité des consommateurs. La compréhension du rôle de l’interface eau/huile dans la texturation des émulsions et son ingénierie constituent des leviers pour mieux contrôler la texture de produits existants. Ils offrent également des pistes pour la création de nouveaux produits correspondant à de nouveaux usages et de nouvelles habitudes de consommation. Les assemblages protéiques façonnés par traitements thermomécaniques permettent d’obtenir des propriétés fonctionnelles adaptées à un usage culinaire cible. Or, ces traitements impactent la structure des protéines et partie de leurs propriétés santé. Pour pleinement répondre aux enjeux de naturalité des produits alimentaires, la préservation des propriétés santé des protéines constitue également un enjeu majeur de l’alimentation de demain. Des pistes sont actuellement à l’étude pour répondre à ce double enjeu de maitrise de la techno-fonctionnalité et de la préservation de la bio-fonctionnalités des protéines