Dulari Jayawardena1, Sangeeta Tyagi1, Ali Nazmi2, Danyvid Olivares-Villagómez2,3, Pradeep K Dudeja4,5. 1. Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA. 2. Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, USA. 3. Vanderbilt Institute for Infection, Immunology and Inflammation, Vanderbilt University Medical Center, Nashville, USA. 4. Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA. pkdudeja@uic.edu. 5. Jesse Brown VA Medical Center, Medical Research Service (600/151), 820 South Damen Avenue, Chicago, IL, 60612, USA. pkdudeja@uic.edu.
Abstract
BACKGROUND: Diarrhea, a major pathological hallmark of inflammatory bowel disease, is characterized by a significant reduction in the expression and function of key intestinal ion transporters. The adoptive naïve CD4+ T cell transfer colitis is an immune-based, chronic colitis mouse model which resembles human Crohn's disease. Although mice with T cell transfer colitis demonstrate diarrhea, the ion transporter basis of this phenotype has not been explored. AIMS/ METHODS: In the current studies, we aimed to determine the mRNA and protein levels of the key NaCl transporters DRA and NHE3 along with the mRNA expression of other transporters in the inflamed intestine. RESULTS: Naïve CD4+ T cells, transferred to Rag2 knockout mice, induced severe colonic inflammation characterized by histological damage and increased mRNA levels of cytokines in the colon with no effect in the ileum. Diarrheal phenotype was a key feature of the excised colons of mice where loose stools were evident. Our results demonstrated that the key chloride transporter DRA, mRNA, and protein levels were significantly reduced in the inflamed colon. However, expression of the key sodium hydrogen exchanger NHE3 was unaffected. The mRNA expression of other important transporters was also determined; in this regard, the sodium channel ENACα and the monocarboxylate transporters MCT1 and SMCT1 mRNA levels were also significantly lower compared to control mice. However, CFTR mRNA was not altered in the colon or ileum. CONCLUSIONS: The studies conducted herein for the first time demonstrate the downregulation of important intestinal ion transporters in proximal and distal colon in T cell transfer colitis mouse model, providing valuable evidence for the ion transporter basis of diarrhea in this chronic model of inflammation.
BACKGROUND:Diarrhea, a major pathological hallmark of inflammatory bowel disease, is characterized by a significant reduction in the expression and function of key intestinal ion transporters. The adoptive naïve CD4+ T cell transfer colitis is an immune-based, chronic colitismouse model which resembles humanCrohn's disease. Although mice with T cell transfer colitis demonstrate diarrhea, the ion transporter basis of this phenotype has not been explored. AIMS/ METHODS: In the current studies, we aimed to determine the mRNA and protein levels of the key NaCl transporters DRA and NHE3 along with the mRNA expression of other transporters in the inflamed intestine. RESULTS: Naïve CD4+ T cells, transferred to Rag2 knockout mice, induced severe colonic inflammation characterized by histological damage and increased mRNA levels of cytokines in the colon with no effect in the ileum. Diarrheal phenotype was a key feature of the excised colons of mice where loose stools were evident. Our results demonstrated that the key chloride transporter DRA, mRNA, and protein levels were significantly reduced in the inflamed colon. However, expression of the key sodium hydrogen exchangerNHE3 was unaffected. The mRNA expression of other important transporters was also determined; in this regard, the sodium channel ENACα and the monocarboxylate transporters MCT1 and SMCT1 mRNA levels were also significantly lower compared to control mice. However, CFTR mRNA was not altered in the colon or ileum. CONCLUSIONS: The studies conducted herein for the first time demonstrate the downregulation of important intestinal ion transporters in proximal and distal colon in T cell transfer colitismouse model, providing valuable evidence for the ion transporter basis of diarrhea in this chronic model of inflammation.
Entities:
Keywords:
DRA; Diarrhea; Inflammatory bowel disease; Ion transporters; T-cell transfer colitis
Authors: Danyvid Olivares-Villagómez; Holly M Scott Algood; Kshipra Singh; Vrajesh V Parekh; Kaitlyn E Ryan; M Blanca Piazuelo; Keith T Wilson; Luc Van Kaer Journal: J Immunol Date: 2011-09-07 Impact factor: 5.422
Authors: H Yang; W Jiang; E E Furth; X Wen; J P Katz; R K Sellon; D G Silberg; T M Antalis; C W Schweinfest; G D Wu Journal: Am J Physiol Date: 1998-12