Enhanced expression of iNOS in inflamed colons of IL-2-deficient mice does not impair colonic epithelial barrier function.
On the basis of recently observed high levels of iNOS expression that correlated with intestinal inflammation in interleukin-2-deficient [IL-2(-/-)] mice, it was postulated that nitric oxide may damage colonic epithelial cells or impair intestinal epithelial barrier function. This damage may result in an increased permeability of the colonic epithelium leading to high antigenic exposure of the intestinal immune system, which may perpetuate chronic inflammation. Our data demonstrate that high expression of iNOS in IL-2(-/-) mice is correlated with the length/weight ratio (L/W ratio), a widely accepted marker for intestinal inflammation. However, no reduction of epithelial resistance was observed, as would be expected in case of a damaged, leaky epithelium. Our results suggest that enhanced formation of NO in IL-2(-/-) mice does not cause impairment of epithelial barrier function.
Harren
M
M
Universitätsklinikum Charité, Humboldt Universität zu Berlin, Campus Virchow-Klinikum, Medical Clinic, Department of Hepatology and Gastroenterology, Berlin, Germany.
Barmeyer
C
C
Schmitz
H
H
Fromm
M
M
Horak
I
I
Dignass
A
A
John
M
M
Wiedenmann
B
B
Schulzke
J D
JD
D000818:Animals; D003092:Colitis / Q000276:immunology / Q000378:metabolism; D003106:Colon / Q000201:enzymology* / Q000276:immunology*; D004553:Electric Conductivity; D017097:Electric Impedance; D004594:Electrophysiology; D015971:Gene Expression Regulation, Enzymologic; D007376:Interleukin-2 / Q000235:genetics*; D007413:Intestinal Mucosa / Q000201:enzymology* / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019001:Nitric Oxide Synthase / Q000235:genetics* / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II
D007376:Interleukin-2; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse