Alterations in intestinal microflora, faecal bile acids and short chain fatty acids in dextran sulphate sodium-induced experimental acute colitis in rats

Background The physiological effects on faecal bile acids and short chain fatty acids (SCFAs) or intestinal microflora in dextran sulphate sodium (DSS)-induced colitis remain unknown and are an area of interest. Design Alterations of these parameters in DSS-induced colitis in rats were evaluated. Methods Male Sprague-Dawley rats (n = 10) were given a 3% DSS aqueous solution orally for 7 days. The concentrations of bile acids and SCFAs in the faeces were measured using gas chromatography and highperformance liquid chromatography. Intestinal microflora, especially anaerobes, were investigated by microbiological methods. Results On day 7, the concentrations of lithocholic acid and alpha -muricholic acid were significantly decreased and that of cholic acid was significantly increased. There was a strong correlation between the concentration of cholic acid and the macroscopic area of damaged tissue in the colon (R = 0.74, P < 0.05). With respect to SCFAs, DSS administration significantly decreased the concentrations of acetic acid and n-butyric acid. There was also some correlation between the concentration of acetic acid and macroscopic damaged area in the colon (R = -0.60, P = 0.07). Bacteriological studies revealed significantly decreased eubacteria, bifidobacteria and total anaerobes after the administration of DSS. In contrast, lactobacilli were significantly increased. Conclusions With the progression of DSS-induced colitis, faecal bile acids, SCFAs and intestinal microflora were altered. It is possible that these alterations contribute in part to the progression of DSS-induced colitis. Eur J Gastroenterol Hepatol 13:107-112 (C) 2001 Lippincott Williams & Wilkins.