Endotoxaemia and cytokine production in experimental colitis.
Systemic endotoxaemia is a well recognized feature of inflammatory bowel disease but its pathogenic role remains uncertain. This study examined plasma endotoxin and cytokine concentrations and the acute-phase protein response in a hapten-induced model of experimental colitis. On days 2, 8 and 14 after induction of colitis with trinitrobenzenesulphonic acid in ethanol (TNBS-E), plasma endotoxin, immunoglobulin (Ig) G and IgM endotoxin-core antibody (EndoCAb), tumour necrosis factor (TNF), interleukin (IL) 6 and alpha 2-macroglobulin (alpha 2M) concentrations and colon macroscopic inflammation score were determined. At all time points there was significant colonic inflammation when compared with control values (P < 0.0001). Animals treated with TNBS-E had raised concentrations of endotoxin at all time points (P < 0.04). In TNBS-E-treated animals EndoCAb concentrations were reduced on day 2 (P < 0.0001) and later increased. There were increases in IL-6 and alpha 2M concentrations in TNBS-E-treated animals but no significant change in TNF concentrations. Endotoxin concentrations correlated with macroscopic inflammation score, IL-6 and alpha 2M concentrations. There was a less consistent correlation between EndoCAb concentrations and these parameters. These results suggest that endotoxin is a mediator of the systemic response in this model of experimental colitis.
Neilly
P J
PJ
Department of Surgery, Queen's University of Belfast, UK.
Gardiner
K R
KR
Kirk
S J
SJ
Jennings
G
G
Anderson
N H
NH
Elia
M
M
Rowlands
B J
BJ
D000818:Animals; D003092:Colitis / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism*; D004731:Endotoxins / Q000097:blood* / Q000378:metabolism; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D015850:Interleukin-6 / Q000378:metabolism; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D016207:Cytokines; D004731:Endotoxins; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha