Mass spectrometry imaging identifies palmitoylcarnitine as an immunological mediator during Salmonella Typhimurium infection

Salmonella Typhimurium causes a self-limiting gastroenteritis that may lead to systemic disease. Bacteria invade the small intestine, crossing the intestinal epithelium from where they are transported to the mesenteric lymph nodes (MLNs) within migrating immune cells. MLNs are an important site at which the innate and adaptive immune responses converge but their architecture and function is severely disrupted during S. Typhimurium infection. To further understand host-pathogen interactions at this site, we used mass spectrometry imaging (MSI) to analyse MLN tissue from a murine model of S. Typhimurium infection. A molecule, identified as palmitoylcarnitine (PalC), was of particular interest due to its high abundance at loci of S. Typhimurium infection and MLN disruption. High levels of PalC localised to sites within the MLNs where B and T cells were absent and where the perimeter of CD169+ sub capsular sinus macrophages was disrupted. MLN cells cultured ex vivo and treated with PalC had reduced CD4+CD25+ T cells and an increased number of B220+CD19+ B cells. The reduction in CD4+CD25+ T cells was likely due to apoptosis driven by increased caspase-3/7 activity. These data indicate that PalC significantly alters the host response in the MLNs, acting as a decisive factor in infection outcome

Probiotic Bacteria Induce a ‘Glow of Health’

Radiant skin and hair are universally recognized as indications of good health. However, this ‘glow of health’ display remains poorly understood. We found that feeding of probiotic bacteria to aged mice induced integumentary changes mimicking peak health and reproductive fitness characteristic of much younger animals. Eating probiotic yogurt triggered epithelial follicular anagen-phase shift with sebocytogenesis resulting in thick lustrous fur due to a bacteria-triggered interleukin-10-dependent mechanism. Aged male animals eating probiotics exhibited increased subcuticular folliculogenesis, when compared with matched controls, yielding luxuriant fur only in probiotic-fed subjects. Female animals displayed probiotic-induced hyperacidity coinciding with shinier hair, a feature that also aligns with fertility in human females. Together these data provide insights into mammalian evolution and novel strategies for integumentary health

Oral Probiotic Control Skin Inflammation by Acting on Both Effector and Regulatory T Cells

Probiotics are believed to alleviate allergic and inflammatory skin disorders, but their impact on pathogenic effector T cells remains poorly documented. Here we show that oral treatment with the probiotic bacteria L. casei (DN-114 001) alone alleviates antigen-specific skin inflammation mediated by either protein-specific CD4+ T cells or hapten-specific CD8+ T cells. In the model of CD8+ T cell-mediated skin inflammation, which reproduces allergic contact dermatitis in human, inhibition of skin inflammation by L. casei is not due to impaired priming of hapten-specific IFNγ-producing cytolytic CD8+ effector T cells. Alternatively, L. casei treatment reduces the recruitment of CD8+ effector T cells into the skin during the elicitation (i.e. symptomatic) phase of CHS. Inhibition of skin inflammation by L. casei requires MHC class II-restricted CD4+ T cells but not CD1d-restricted NK-T cells. L casei treatment enhanced the frequency of FoxP3+ Treg in the skin and increased the production of IL-10 by CD4+CD25+ regulatory T cells in skin draining lymph nodes of hapten-sensitized mice. These data demonstrate that orally administered L. casei (DN-114 001) efficiently alleviate T cell-mediated skin inflammation without causing immune suppression, via mechanisms that include control of CD8+ effector T cells and involve regulatory CD4+ T cells. L. casei (DN-114 001) may thus represent a probiotic of potential interest for immunomodulation of T cell-mediated allergic skin diseases in human

Utilisation de quelques marqueurs physiologiques et biochimiques dans l’expression de tolérance au stress hydrique chez 10 génotypes de blé dur (Triticum durum Desf )

Ne pouvant lutter ou édifier une stratégie contre les facteurs  incontournables de l’environnement, l’homme a essayé de domestiquer des plantes qui ont pu progressivement s’adapter aux contraintes  imposées. Parmi les voies préconisées, la gestion rationnelle des  ressources naturelles, notamment hydriques, figurent parmi les plus privilégiées. L’exploration des mécanismes physiologiques d’adaptation au déficit hydrique chez les céréales permet d’en sélectionner quelques uns pour enfin les introduire dans un programme national d’intensification. A cet effet, dix génotypes de blé dur ont fait l’objet d’étude au plan  physiologique, biochimique, histologique ainsi que sur le plan de la vigueur et la viabilité des semences. Les résultats montrent que l’essai  topographique au Tétrazolium semble accorder une plus grande vigueur chez les génotypes 1, 3 et 4. L’étude histologique met en valeur les variétés 1, 4, 5, 9, 10 qui montrent une bonne présentation de tous les tissus et ce, sous conditions de stress hydrique. Les osmoprotecteurs tels que la proline et les sucres solubles augmentent avec le stress,  démontrant ainsi leur rôle de tolérance ou forme adaptative. La  turgescence enfin, montre que V1 et V8 sont plus efficientes à gérer  l’échange hydrique foliaire.Mots clés : Blé dur - Déficit hydrique - Adaptation - Physiologie - GénétiqueAs long as man enables to build a strategy against environmental factors, he tried to domesticate plants which were progressively able to be adapted to those imposed constraints. Among those ways, efficient use of natural resources, water resources in particular, was a prevalent mean. Adaptative physiological mechanisms exploration to water deficit for cereals has  permitted to select some of them in order to incorporate them within  national intensification program. For this purpose, ten genotypes of durum wheat have been submitted to physiological, biochemical, histological study and viability and seed vigor as well. Results that have been obtained show that Tetrazolium test seems to accord a greater seed vigor for genotypes 1, 3, and 4. Histological study points out varieties 1, 4, 5, 9, and 10 which show a good presentation of all tissues under water stress conditions. Osmoprotectors, such as free proline and soluble sugars have increased with stress. This enables us to confirm tolerance role or adaptative pathway. Cell turgor show that V1 and V8 are more efficient for water exchanges and equilibrium in leaves.Keywords : Durum wheat – Water deficit- Adaptation-Physiology - Geneti

Ethnopharmacological survey and phytochemical screening of some medicinal Asteraceae from Algerian Sahara

A first report of Asteracea species census of the Algerian folk medicine, currently used in Sahara for the treatment of illenes is presented. 11 Asteraceae species namely: Anvillea radiata coss, Artemisia herba-alba, Brocchia cinerea, Bubonium graveolens, Cotula anthemoides, Echinops spinosus, Launaea arborescens, Launaea nudicaulis, Launaea resedifolia, Scorzonera undulata and Warionia saharae were selected based on the survey through interviews with local inhabitant, herbalist in the Souk and old women according to our previous works. Ethnopharmacolgical potential and chemical constituents of this species are described