Effects of Probiotics on Serum Bile Acids in Patients With Ulcerative Colitis

Abstract

BACKGROUND/AIM: Evaluation of bile acids (BA) is a useful method for assessing changes of the intestinal flora in patients with ulcerative colitis (UC). During enterohepatic circulation, conjugated BA is deconjugated to free BA by intestinal bacteria. The presence of intestinal microflora (Clostridium and Eubacterium) leads to 7 alpha-dehydroxylation of cholic acid (CA) and chenodeoxycholic acid (CDCA), yielding deoxycholic acid (DCA) and lithocholic acid, respectively. It was reported that the Lachnospiraceae subgroup of Firmicutes (including Clostridium) are decreased in the colon of UC patients compared to controls without inflammatory bowel disease. We have already reported that the serum%CDCA is significantly higher in patients with UC than in healthy volunteers (HV), while serum%DCA is significantly lower in UC patients than in HV, and these changes do not depend on the activity or extent of UC. The aim of the present study was to elucidate the effects of probiotics in patients with UC by examining the serum BA profile. PATIENTS/METHODS: The study population was 27 patients in whom UC was diagnosed from endoscopic and histological findings. All patients underwent ileocolonoscopy with appropriate biopsies. They were divided into the following 2 groups based on endoscopic findings: 15 patients with distal UC (dUC) and diffuse changes extending from the rectum to the splenic flexure, and 12 patients with more extensive UC or pancolitis (pUC). Treatment was givenwithmesalazine or salazosulfapyridine (5-ASA) and all patients achieved remission. After entering remission, they were treated with by 5-ASA plus the probiotic Clostridium butyricum Miyairi (MIYA) (3 g/day) for 4 weeks. The control group was composed of 8 HV. Routine laboratory tests were performed on the basis of clinical need, while fasting serum samples for measurement of BA were obtained before and after treatment with 5-ASA plus MIYA for 4 weeks. Serum BA fractions were analyzed by HPLC. RESULTS: There were no significant differences of serum total BA among the 3 groups. Before treatment, %CDCA was significantly higher in the dUC and pUC groups than in the HV group, while %DCA was significantly lower than in the HV group. In the pUC group, %CDCA was significantly higher and %DCA was significantly lower than in the HV group after 4 weeks of probiotic treatment. In the dUC group, however, there was no significant difference of %CDCA or %DCA after 4 weeks compared with the HV group. There were no significant differences in the ratio of conjugated BA to total serum BA among the three groups. CONCLUSIONS: These results suggest that intestinal bacteria involved in the deconjugation of BA are restored when patients achieve remission of UC by treatment with 5-ASA, and thatMIYA restoredmicroflora involved in 7 alpha-dehydroxylation in the dUC group, but not in the pUC group.