Project description:Ulcerative colitis (UC) is a life-threatening heterogeneous condition characterized by inflammation of the colon. Endoplasmic reticulum aminopeptidase 1 (ERAP1) is essential for antigen processing and immune regulation, however, its specific role in UC pathogenesis and therapeutic response remains unclear. This study aimed to investigate the role of ERAP1 in the response to sulfasalazine, a standard treatment for UC, using an ERAP1-heterozygous (ERAP1⁺/⁻) mouse model susceptible to colitis. Wild-type (WT) and ERAP1+/− mice were treated with 2.5% dextran sulfate sodium (DSS) to induce colitis, followed by sulfasalazine administration. Colitis severity was assessed through histopathology. Immune cell populations, including neutrophils, dendritic cells, T cells, and NK1.1+ cells, were analyzed using flow cytometry. RNA sequencing of colonic tissues was performed to assess gene expression changes associated with reduced ERAP1 expression. ERAP1+/− mice exhibited more severe DSS-induced colitis, with greater weight loss and increased mucosal damage compared to WT mice. In addition, ERAP1+/− colitis mice showed marked changes in peripheral blood and intestinal intraepithelial lymphocyte (IELs) immune cell infiltration after sulfasalazine treatment. RNA sequencing identified 428 differentially expressed genes between ERAP1⁺/⁻ and WT mice. Among these, 28 genes were previously associated with colitis or colorectal cancer, of which 11 were upregulated and 17 downregulated in ERAP1⁺/⁻ mice. RT-qPCR analysis further confirmed that the expression of Anxa9, Atp2a1, and Hepacam2 was significantly elevated in ERAP1⁺/⁻ mice following sulfasalazine treatment, suggesting a differential therapeutic response. Collectively, our study demonstrates that partial ERAP1 deficiency exacerbates DSS-induced colitis by promoting immune dysregulation and altering the expression of inflammation-related genes. These findings suggest that reduced ERAP1 expression may impair the therapeutic efficacy of sulfasalazine. Therefore, ERAP1 may serve as a key regulator in the pathogenesis of UC and a potential target for therapy.
Project description:The goal of this project is to investigate the mechanisms through which high fat diet (HFD) exacerbates colitis via the liver-gut axis, particularly focusing on liver dysregulated lipid metabolism and intestinal autophagy. We examined colon transcriptomes of C57BL6/J mice fed a control diet (CD) or HFD with or without dextran sulfate sodium (DSS) by RNA seq analysis.
Project description:The goal of this project is to investigate the mechanisms through which high fat diet (HFD) exacerbates colitis via the liver-gut axis, particularly focusing on liver dysregulated lipid metabolism and intestinal autophagy. We examined liver transcriptomes of C57BL6/J mice fed a control diet (CD) or HFD with or without dextran sulfate sodium (DSS) by RNA seq analysis.
Project description:Rats were randomly assigned to one of three different groups, a control (C, n=6) group that received a saline enema, a TNBS group (n=3) that received the TNBS challenge and a SAZ group (n=3) that received 500 mg/kg·day of sulfasalazine in 1% methylcellulose by oesophageal gavage. The control and TNBS groups received no treatment since they were also part of a separate experiment. All animals were sacrificed by cervical dislocation 7 days after colitis induction.
Project description:Paneth cells, intestine-originated innate immune-like cells, are important for maintenance of the intestinal stem cell niche, gut microbiota, and gastrointestinal barrier. Dysfunctional Paneth cells under pathological conditions are a site of origin for intestinal inflammation. However, mechanisms underlying stress-induced Paneth cell dysregulation remains unclear. We have previously reported that deletion of SIRT1 in the intestinal epithelium (SIRT1 iKO) leads to hyperaction of Paneth cells along with an increased sensitivity to Dextran sodium sulfate (DSS)-induced colitis. We recently generated a Paneth-cell specific SIRT1 KO mouse model (SIRT1 PKO). Similar to mice with SIRT1 iKO mice, SIRT1 PKO mice had increased abundance as well as hyperactivation of Paneth cells in vivo and in cultured intestinal organoids. However, in contrast to the hypersensitivity of SIRT1 iKO mice to chemical- or age-induced inflammation, SIRT1 PKO mice were protected from Dextran sodium sulfate (DSS)-colitis.
Project description:We reported the gene expression profiles of hCYP1A mouse colitis epithelial tissues on Day 1, 3 and 7 after the treatment with DSS or DSS/PhIP for 5 days.