Intestinal microbiota in human health and disease: the impact of probiotics

The complex communities of microorganisms that colonise the human gastrointestinal tract play an important role in human health. The development of culture-independent molecular techniques has provided new insights in the composition and diversity of the intestinal microbiota. Here, we summarise the present state of the art on the intestinal microbiota with specific attention for the application of high-throughput functional microbiomic approaches to determine the contribution of the intestinal microbiota to human health. Moreover, we review the association between dysbiosis of the microbiota and both intestinal and extra-intestinal diseases. Finally, we discuss the potential of probiotic microorganism to modulate the intestinal microbiota and thereby contribute to health and well-being. The effects of probiotic consumption on the intestinal microbiota are addressed, as well as the development of tailor-made probiotics designed for specific aberrations that are associated with microbial dysbiosis

Distinct Microbiome in Pouchitis Compared to Healthy Pouches in Ulcerative Colitis and Familial Adenomatous Polyposis

Background: Pouchitis occurs in up to 50% of patients with ulcerative colitis (UC) undergoing ileal pouch anal anastomosis (IPAA). Pouchitis rarely occurs in patients with familial adenomatous polyposis (FAP) who undergo IPAA. Our aim was to compare mucosal and luminal flora in patients with UC-associated pouchitis (UCP), healthy UC pouches (HUC), and healthy FAP pouches (FAP). Methods: Nineteen patients were enrolled in thi s cross-sectional study (nine UCP, tl1ree HUC, seven FAP). Patie nts with active pouchitis were identified using the Pouchitis Disease Activity Index (PDAI). Ileal pouch mucosal biopsies and fecal samples were analyzed with a 16S rDNA-based terminal restriction fr agment length polymorphism (TRFLP) approach. Pooled fecal DNA from four UCP and four FAP pouches were sequenced for further speciation. Results: TRFLP data revealed statistically significant diffe rences in the mucosal and fecal microbiota between each group of patients. UCP samples exhibited significantly more TRFLP peaks matching Clostridium and Eubacterium genera compared to HUC and FAP pouches and fewer peaks matching Lactobacillus and Streptococcus genera compared to FAP. DNA Sanger sequencing of a subset of luminal samples revealed UCP having more identifiable sequences of Firmicutes (51.2% versus 2 1.2%) and Verrucomicrobia (20.2% versus 3.2%), and fewer Bacteroidetes (1 7.9% versus 60.5%) and Proteobacteria (9.8% versus 14.7%) compared to FAP. Conclusions: The pouch microbial environment appears to be distinctly different in the settings of UC pouchitis, healthy UC, and FAP. These findings suggest that a dysbiosis may exist in pouchitis which may be central to understanding the disease

Distinct microbiome in pouchitis compared to healthy pouches in ulcerative colitis and familial adenomatous polyposis

Background: Pouchitis occurs in up to 50% of patients with ulcerative colitis (UC) undergoing ileal pouch anal anastomosis (IPAA). Pouchitis rarely occurs in patients with familial adenomatous polyposis (FAP) who undergo IPAA. Our aim was to compare mucosal and luminal flora in patients with UC-associated pouchitis (UCP), healthy UC pouches (HUC), and healthy FAP pouches (FAP). Methods: Nineteen patients were enrolled in this cross-sectional study (nine UCP, three HUC, seven FAP). Patients with active pouchitis were identified using the Pouchitis Disease Activity Index (PDAI). Ileal pouch mucosal biopsies and fecal samples were analyzed with a 16S rDNA-based terminal restriction fragment length polymorphism (TRFLP) approach. Pooled fecal DNA from four UCP and four FAP pouches were sequenced for further speciation. Results: TRFLP data revealed statistically significant differences in the mucosal and fecal microbiota between each group of patients. UCP samples exhibited significantly more TRFLP peaks matching Clostridium and Eubacterium genera compared to HUC and FAP pouches and fewer peaks matching Lactobacillus and Streptococcus genera compared to FAP. DNA Sanger sequencing of a subset of luminal samples revealed UCP having more identifiable sequences of Firmicutes (51.2% versus 21.2%) and Verrucomicrobia (20.2% versus 3.2%), and fewer Bacteroidetes (17.9% versus 60.5%) and Proteobacteria (9.8% versus 14.7%) compared to FAP. Conclusions: The pouch microbial environment appears to be distinctly different in the settings of UC pouchitis, healthy UC, and FAP. These findings suggest that a dysbiosis may exist in pouchitis which may be central to understanding the disease. (Inflamm Bowel Dis 2011;17:1092-1100