Project description:Temporal genome profiling of DSS colitis The DSS induced mouse colitis model is often used to emulate Ulcerative Colitis (UC) in order understand pathophysiological mechanism of inflammatory bowel disease (IBD). Given the progressive nature of IBD, colon tissue gene expression changes during the evolution of disease, and knowing the changes in gene expression profiles could indentify potential diagnostic markers or additional therapeutic targets for colitis. Therefore, we performed temporal genome expression profiling analysis using the Affymetrix genome wide microarray system to identify broad scale changes in gene expression associated with the development of colitis. Keywords: Expression time course of mouse colon tissue induced by 3% DSS. C57BL/6J mice were given 3% DSS in the drinking water and tissues from individual cohorts were collected at days 0, 2, 4 and 6. Total RNA were extracted from the colon tissue and detected by Affymerix GeneChip Mouse Genome 430 2.0 Array.
Project description:Gene expression analysis of sorted colon macrophages of Rictor fl/fl LysM+/+ and Rictor fl/fl LysM+/cre mice Dysregulations of immune and metabolic processes can lead to chronic inflammation, which is one of the driving forces for the development of cancer. Macrophages are regulators of these processes and therefore have a fundamental role for the initiation of cancer. Here we find that deletion of Rictor in myeloid cells increases tumor number and size in the colitis-associated colorectal cancer model and leads to a stronger inflammatory response in the underlying acute DSS-colitis model. OPN is shown to be upregulated in the serum of myeloid-specific Rictor-KO mice during the DSS-colitis and the more severe phenotype, characterized by decreased survival, increased weight loss, shorter colons and enhanced infiltration of immune cells into the colon, can be reverted by the neutralization of OPN in these mice. Microarray analysis reveals a change in inflammatory and metabolic gene signatures of Rictor-KO colon macrophages that is also seen in the Rictor-KO BMDM in vitro. Therefore, our data show that myeloid Rictor controls macrophage polarization and the cellular energy metabolism, thereby suppressing colitis and colitis-associated colorectal cancer.
Project description:To investigate the detailed molecular mechanisms for the regulatory role of Nik in colitis, microarray gene expression analysis was performed on colon tissue RNA isolated from 3-month-old untreated control and DSS treated Nik+/+ and NikΔIE mice.
Project description:Temporal genome profiling of DSS colitis The DSS induced mouse colitis model is often used to emulate Ulcerative Colitis (UC) in order understand pathophysiological mechanism of inflammatory bowel disease (IBD). Given the progressive nature of IBD, colon tissue gene expression changes during the evolution of disease, and knowing the changes in gene expression profiles could indentify potential diagnostic markers or additional therapeutic targets for colitis. Therefore, we performed temporal genome expression profiling analysis using the Affymetrix genome wide microarray system to identify broad scale changes in gene expression associated with the development of colitis. Keywords: Expression time course of mouse colon tissue induced by 3% DSS.
Project description:Primary cilia (PC) are important signaling hubs in cells and we explored their role in colorectal cancer (CRC) and colitis. In the colon we found PC to be mostly present on different subtypes of fibroblasts and exposure of mice to either chemically induced colitis-associated colon carcinogenesis (CAC) or dextran sodium sulfate (DSS)-induced acute colitis decreased PC numbers. We employed conditional knock-out strains for the PC essential genes, Kif3A and Ift88, to generate mice with reduced numbers of PC on colonic fibroblasts. These mice showed an increased susceptibility in the CAC model as well as in DSS-induced colitis. Secretome and immunohistochemical analyses of DSS-treated mice displayed an elevated production of the pro-inflammatory cytokine IL-6 in PC-deficient colons. An inflammatory environment diminished PC presence in primary fibroblast cultures. This was triggered by IL-6 as identified by RNAseq analysis together with blocking experiments, suggesting an activation loop between IL-6 production and PC loss. Notably, an analysis of PC presence on biopsies of patients with ulcerative colitis as well as CRC patients revealed decreased numbers of PC on colonic fibroblasts in pathological versus surrounding normal tissue. Taken together, we provide evidence that a decrease in colonic PC numbers promotes colitis and CRC.
Project description:Analysis of gene expression of colon or ileum tissue of germfree, germfree mice colonized with SPF microbiota at 5 weeks of age, and SPF mice at 6 or 10 weeks of age under health and DSS colitis
Project description:This study identifies a novel mechanism linking IL-17A with colon tissue repair and tumor development. Abrogation of IL-17A signaling mice attenuated tissue repair of DSS-induced damage in colon epithelium and markedly reduced tumor development in AOM/DSS model of colitis-associated cancer. The goal of these studies is to identify genes associated with IL-17RC deficiency during AOM-DSS induced tumorigenesis
Project description:To find out which miRNAs are significantly differential expression and potentially involved in the process of inflammation promoting carcinogenesis of colorectal cancer (CRC). We established a colitis-associated CRC (AOM/DSS, Azoxymethane/Dextran sulfate sodium salt) model, colitis (DSS) model and high dose carcinogen (AOM, about 5 times AOM amount given than AOM/DSS model) model. At day 100 when tumor formed in AOM/DSS bearing mice (colitis-associated CRC mice) but no tumor was found in AOM (high dose carcinogen) and DSS model, we employed miRNA microarray as a discovery platform to identify genes with the potential to involve in the progression of CRC promoted by inflammation. 5-7 weeks female BALB/c mice, (1) AOM/DSS group: AOM 12.5mg/kg i.p. at day 1, DSS drinking 5d/21dx3circles from day 5; (2) AOM group: AOM 10mg/kg i.p. 1/weekx6 from day 1; (3) DSS group: DSS drinking 5d/21dx3circles from day 5. The distal colon epithelial tissues were collected at day100 when tumor formed in AOM/DSS bearing mice. The miRNA microarray experiments were performed together.
Project description:Ribo-zero RNAseq experiments were carried out with mouse distal colon DSS Colitis model of genetically engineered mice. For each mouse line for: Gpsm3 (3% DSS), Aif1 (3% DSS), Nckap1l (Hem1), Dock2 (3% DSS), Dok3 (3.5% DSS) DSS treatment for five days followed by water for 5 days, (7 days for Nckap1l). Tissue was collected at Day 10 (Day 12 for Nckap1l (HEM1)).
Project description:The identification of inflammatory bowel disease (IBD) susceptibility genes by genome-wide association has linked this pathology to autophagy, a lysosomal degradation pathway that is crucial for cell and tissue homeostasis. Here, we describe autophagin-1 (ATG4B) as an essential protein in the control of inflammatory response during experimental colitis. In this pathological condition, ATG4B protein levels increase paralleling the induction of autophagy. Moreover, ATG4B expression is significantly reduced in affected areas of the colon from IBD patients. Consistently, atg4b-/- mice present Paneth cell abnormalities, as well as an increased susceptibility to DSS-induced colitis. Atg4b-deficient mice exhibit significant alterations in proinflammatory cytokines and mediators of the immune response to bacterial infections, which are reminiscent of those found in patients with Crohn’s disease or ulcerative colitis. Additionally, antibiotic treatments and bone marrow transplantation from wild-type mice reduced colitis in atg4b-/- mice. Taken together, these results provide additional evidence on the importance of autophagy in intestinal pathologies and describe ATG4B as a novel protective protein in inflammatory colitis. Finally, we propose that Atg4b-null mice are a suitable model for in vivo studies aimed at testing new therapeutic strategies for intestinal diseases associated with autophagy deficiency Seven samples were collected in total: three from wild-type mice (1 from the ileum and the colon of control mice, and 1 from the colon of a DSS-treated mouse) and four from Atg4b knock-out mice (1 from the ileum and the colon of control mice, and 2 from the colon of DSS-treated mice).