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 f atty 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 solut ion orally for 7 days. The concentrations of bile acids and SCFAs in the fa eces were measured using gas chromatography and highperformance liquid chro matography. Intestinal microflora, especially anaerobes, were investigated by microbiological methods. Results On day 7, the concentrations of lithocholic acid and alpha -muricho lic acid were significantly decreased and that of cholic acid was significa ntly 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 dec reased 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 re vealed significantly decreased eubacteria, bifidobacteria and total anaerob es after the administration of DSS. In contrast, lactobacilli were signific antly increased. Conclusions With the progression of DSS-induced colitis, faecal bile acids, SCFAs and intestinal microflora were altered. It is possible that these al terations contribute in part to the progression of DSS-induced colitis. Eur J Gastroenterol Hepatol 13:107-112 (C) 2001 Lippincott Williams & Wilkins.