A86 NON-PREBIOTIC EFFECTS OF RHAMNOGALACTURONAN ON INTESTINAL EPITHELIAL BARRIER FUNCTION AND WOUND HEALING
Notice bibliographique
Résumé
Dietary fibre comprises a complex group of polysaccharides that are indigestible but are fermented by gut microbiota, promoting beneficial effects to intestinal mucosa indirectly. However, studies have shown that polysaccharides also have direct effects on intestinal epithelial barrier function. Recently, we found that rhamnogalacturonan (RGal), a polysaccharide isolated from Acmella oleracea, protected mice against DSS colitis. However, the underlying mechanism of action of RGal remains unclear. We aimed to verify whether RGal directly enhances intestinal epithelial barrier function and promotes wound healing to maintain tissue health. Monolayers of human colonic epithelial Caco-2 cells were mounted in Ussing chambers and treated apically with RGal (10–1000 µg/ml). Transepithelial electrical resistance (TER) and FITC-dextran flux were measured. In a calcium-switch assay, the epithelial monolayers were temporarily exposed to zero calcium conditions (calcium-free buffer containing the calcium chelator, EGTA) to disassemble tight junctions. RGal (10–1000 µg/ml) was added during calcium-free conditions and its effect on barrier recovery during the return to Ca-containing buffer was assessed. FITC-dextran permeability was also evaluated in Caco-2 cells stimulated with IFNg plus TNF-a (25 ng/ml, basolateral) and co- or post-treated with RGal (1000 µg/ml, apical) for 48 or 24 h, respectively. Immunofluorescence staining was performed for evaluation of tight junction proteins, occludin and ZO-1. Finally, to evaluate wound healing, scratch wounds were performed on cell monolayers treated with RGal (10–1000 µg/ml) at 0 and 24 h. Wound healing was assessed over 48 h using the IncuCyte live cell imaging system. Apical treatment of cells with RGal (1000 µg/ml) significantly increased TER and reduced FITC-dextran flux compared to control. Additionally, apical addition of RGal accelerated tight junction reassembly in the calcium switch assay. Exposure to cytokines enhanced FITC-dextran flux and disrupted tight junction protein localization. Co- and post-treatment of cells with RGal (1000 µg/ml) reversed this effect on FITC-dextran flux by 13 and 16% at 60 min, respectively, and preserved the occludin and ZO-1 distribution. In the wound healing assay, RGal at concentration of 1000 µg/ml enhanced wound healing by 28% at 48 h compared to control group, under 10% serum but not serum free conditions. We demonstrated that RGal increased barrier function through acceleration of tight junction assembly, prevented cytokine-induced barrier dysfunction, and was able to increase wound healing in vitro. Elucidation of RGal mechanisms of action could lead to new approaches to the treatment of inflammatory diseases of the gut that are characterized by compromised epithelial barrier function. CIHR
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».