Project description:Deoxynivalenol (DON) is a frequent mycotoxin in grains, produced by Fusarium fungi, which demonstre multiple side effects such as modulation of immune responses, reduced feed intake and weight gain or impairment of the intestinal barrier function. Among animal species, pigs are the best model for humans and are very sensitive to DON. In wheat, DON can be conjugated to glucose to form DON-3-β-D-glucoside (D3G). Some bacteria isolated from digestive tracts or soil, are also able to de-epoxydize or epimerize DON to metabolites such as deepoxy-deoxynivalenol (DOM-1) or 3-epi-deoxynivalenol (epi-DON). The toxicity of these DON metabolites is poorly documented. By the way of ingestion, the intestine is the first organ exposed to these molecules and so constitute a relevant model. The aim of this study was to compare the intestinal toxicity of three DON metabolites (D3G, DOM-1 and epi-DON) with the one of DON. Intestinal explants from 6 pigs were treated with 10mM DON, D3G, DOM-1 or epi-DON for 4 hours and transcriptomic analysis was performed using an âAgilent Porcinet 60Kâ. Jejunal explants from 4 piglets aged of 5 weeks were sampled and exposed in vitro to differents molecules (DON, D3G, DOM-1 & 3-epi-DON) at 10µM during 4h. Then RNA was extracted.
Project description:Deoxynivalenol (DON) is a frequent mycotoxin in grains, produced by Fusarium fungi, which demonstre multiple side effects such as modulation of immune responses, reduced feed intake and weight gain or impairment of the intestinal barrier function. Among animal species, pigs are the best model for humans and are very sensitive to DON. In wheat, DON can be conjugated to glucose to form DON-3-β-D-glucoside (D3G). Some bacteria isolated from digestive tracts or soil, are also able to de-epoxydize or epimerize DON to metabolites such as deepoxy-deoxynivalenol (DOM-1) or 3-epi-deoxynivalenol (epi-DON). The toxicity of these DON metabolites is poorly documented. By the way of ingestion, the intestine is the first organ exposed to these molecules and so constitute a relevant model. The aim of this study was to compare the intestinal toxicity of three DON metabolites (D3G, DOM-1 and epi-DON) with the one of DON. Intestinal explants from 6 pigs were treated with 10mM DON, D3G, DOM-1 or epi-DON for 4 hours and transcriptomic analysis was performed using an “Agilent Porcinet 60K”.
Project description:To assess the role of LSD1 in human intestinal epithelium, human small intestinal organoids were treated with an inhibitor for LSD1 (GSK-LSD1) and compared to untreated organoids. The organoids were grown with specific conditions where Paneth cells are present in the organoids as similar experiments in mice show that Paneth cells disappear upon GSK-LSD1 treatment. Similar to mouse intestinal organoids, Paneth cells dissappear upon GSK-LSD1 treatment. Furthermore, we used these gene set enrichment analysis on these microarray data to show that these human intestinal organoids have a similar phenotype as mice epithelium without LSD1.
Project description:To assess the role of LSD1 in mice small intestinal epithelium, small intestinal organoids were treated with an inhibitor for LSD1 (GSK-LSD1) and compared to untreated organoids. Similar to intestinal epithelium from mice with an intestinal epithelium specific LSD1-KO, paneth cells dissappear upon GSK-LSD1 treatment. We used these sequencing data to show that these small intestinal organoids have a similar phenotype as mice epithelium without LSD1.
Project description:Heligmosomoides polygyrus is a natural intestinal parasite of mice which exerts wide ranging modulatory effects on the immune system. This experiment was designed to investigate its abillity to modify intestinal epithelial cells, which form part of its natural niche. We tested gene expression in vitro, in differentiating organoids of small intestinal origin, exposed to cytokines and the released products of the parasite, termed HpES.
Project description:Stomach and intestinal adult epithelia harbor stem cells that are responsible for their continuous regeneration. Stomach and intestinal stem cells differ in their differentiation program and in the gene repertoire that they express. We show that single adult Lgr5-positive stem cells, isolated from 3D cultured small intestinal organoids, require Cdx2 to maintain their intestinal identity and are converted cell-autonomously into stomach-pyloric stem cells in the absence of this transcription factor. In order to obtain Cdx2null intestinal stem cells carrying the Lgr5-EGFP marker, 5-6 days old small intestinal organoids generated from Cdx2-/fl/Lgr5-EGFP-Ires-CreERT2 mice were incubated with 1 µM of 4-hydroxytamoxifen in intestinal culture medium for 16h to activate the Cre recombinase. Controls were 4-hydroxytamoxifen-untreated small intestinal (Control SI) and stomach (Control Sto) organoids issued from mice with the same genotype. The organoids were dissociated and sorted for EGFPhi. Cdx2null, Control SI and Control Sto clonal organoids were generated and expanded from Lgr5-EGFPhi single cells in stomach specific culture medium (ENRWfg) and RNA was isolated for RNA-Seq analysis. Cdx2+ Stomach (Sto) organoids were generated by infection of the wild type stomach organoids with lentiviral stock expressing Cdx2. They were cultured in stomach medium (ENRWfg) and RNA was isolated for RNA-Seq analysis
Project description:To study the effects of rifaximin on human small intestinal (hSI) organoids, we performed RNAseq in PXR knockdown hSI compared to control hSI.
Project description:The endodermal lining of the adult gastro-intestinal tract harbors stem cells that are responsible for the day-to-day regeneration of the epithelium. Stem cells residing in the pyloric glands of the stomach and in the small intestinal crypts differ in their differentiation program and in the gene repertoire that they express. Both types of stem cells have been shown to grow from single cells into 3D structures (organoids) in vitro. We show that single adult Lgr5-positive stem cells, isolated from small intestinal organoids, require Cdx2 to maintain their intestinal identity and are converted cell-autonomously into pyloric stem cells in the absence of this transcription factor. Clonal descendants of Cdx2null small intestinal stem cells enter the gastric differentiation program instead of producing intestinal derivatives. Conversely, forced expression of Cdx2 in gastric organoids results in their intestinalization. The intestinal genetic program is thus critically dependent on the single transcription factor encoding gene Cdx2. Small intestinal crypts and stomach glands were isolated from Cdx2-/fl / Lgr5-EGFP-CreERT2 mice and cultured for a week in order to generate small intestinal (SI) and stomach (Sto) in vitro organoids. The Lgr5-CreERT2 enzyme activity has been induced by overnight 4-hydroxytamoxifen induction. Tamoxifen treated and untreated Lgr5-EGFPhi SI and Sto stem cells were FACS sorted and seeded back into ENRWfg (Sto med) culture conditions in order to generate Cdx2-/fl small intestinal (Control SI), Cdx2null small intestinal (Cdx2null SI) and Cdx2-/fl stomach (Control Sto) clonal organoids. Cdx2-/fl SI organoids and Cdx2-/fl Sto organoids have been also cultured in ENR (SI med) to induce differentiation. After some passages of clonal organoid expansion, RNA was isolated from Control SI, Cdx2null SI and Control Sto Lgr5-EGFPhi FACS sorted stem cell populations and from smal intestinal and stomach organoids cultured in different conditions and hybridized on Affymetrix Mouse Gene ST 1.1 arrays.