Biomarkers of human gastrointestinal tract regions

Dysregulation of intestinal epithelial cell performance is associated with an array of pathologies whose onset mechanisms are incompletely understood. While whole-genomics approaches have been valuable for studying the molecular basis of several intestinal diseases, a thorough analysis of gene expression along the healthy gastrointestinal tract is still lacking. The aim of this study was to map gene expression in gastrointestinal regions of healthy human adults and to implement a procedure for microarray data analysis that would allow its use as a reference when screening for pathological deviations. We analyzed the gene expression signature of antrum, duodenum, jejunum, ileum, and transverse colon biopsies using a biostatistical method based on a multivariate and univariate approach to identify region-selective genes. One hundred sixty-six genes were found responsible for distinguishing the five regions considered. Nineteen had never been described in the GI tract, including a semaphorin probably implicated in pathogen invasion and six novel genes. Moreover, by crossing these genes with those retrieved from an existing data set of gene expression in the intestine of ulcerative colitis and Crohn's disease patients, we identified genes that might be biomarkers of Crohn's and/or ulcerative colitis in ileum and/or colon. These include CLCA4 and SLC26A2, both implicated in ion transport. This study furnishes the first map of gene expression along the healthy human gastrointestinal tract. Furthermore, the approach implemented here, and validated by retrieving known gene profiles, allowed the identification of promising new leads in both healthy and disease state

Degraded Carrageenan Causing Colitis in Rats Induces TNF Secretion and ICAM-1 Upregulation in Monocytes through NF-κB Activation

Carrageenan (CGN) is a high molecular weight sulphated polysaccharide derived from red seaweeds. In rodents, its degraded forms (dCGN) can induce intestinal inflammation associated with macrophage recruitment and activation. The aim of this study was: 1) to analyze the size-dependent effects of dCGN on colon inflammation in vivo, and 2) to correlate these effects with monocyte/macrophage proliferation, cytokine production and expression of various cell surface antigens including ICAM-1 adhesion molecule. Peripheral blood monocytes (PBM) and THP-1 monocytic cells were cultured in the presence of either 10 or 40 kDa, dCGN. The 40 kDa, but not the 10 kDa dCGN, induced colitis in in vivo. Degraded CGN inhibited THP-1 cell proliferation in vitro, arresting the cells in G1 phase. In addition, dCGN increased ICAM-1 expression in both PBM and THP-1 cells with a major effect seen after 40 kDa dCGN exposure. Also, dCGN stimulated monocyte aggregation in vitro that was prevented by incubation with anti-ICAM-1 antibody. Finally, dCGN stimulated TNF-α expression and secretion by both PBM and THP-1 cells. All these effects were linked to NF-κB activation. These data strongly suggest that the degraded forms of CGN have a pronounced effect on monocytes, characteristic of an inflammatory phenotype

Mission sur l’écosystème de la recherche et de l’innovation 14 propositions pour engager le processus de rénovation et de simplification de l’écosystème national Rapport à Madame la Ministre de l’Enseignement supérieur et de la Recherche

Mme la Ministre Sylvie Retailleau a confié à M. Philippe Gillet cette mission par lettre en date du 1er décembre 2022 (voir annexe). Après une phase de cadrage, les travaux ont été menés par l’ensemble du groupe de travail composé de Mmes Christine Cherbut et Véronique Perdereau et MM. Yves Caristan et Patrick Lévy de janvier à mai 2023. Les membres de la mission ont été appuyés par un inspecteur général de l’éducation, du sport et de la recherche, M. Charles Persoz. Cette mission s’est inscrite dans un contexte évolutif : la LPR a eu des conséquences récentes, plusieurs programmes stratégiques ont été initiés quelques mois ou quelques semaines avant le démarrage de la mission, comme les PEPR, les PUI, le programme de recherche à risque

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8.1. Quelles évolutions pour le consommateur ?

Hungry Planet – Familles du monde. La famille Sobczynscy (Konstancin-Jeziorna, Pologne), pose avec sa consommation alimentaire hebdomadaire. Budget : 151,20 $. Photo Peter Menzel / Cosmos « Il y a peu de différence entre un être humain et un autre, mais c’est cette différence qui est tout » a dit le philosophe américain William James. La « customisation »* des produits de consommation est une tendance marketing forte. Cette tendance pourrait être durable, répondant au désir du consom..

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