Crohn’s disease (CD) is a chronic inflammatory condition of the gastrointestinal tract and its aetiology still remains unknown. In the last years, it has been shown the clinical efficacy of rifaximin, a poorly absorbed and broad-spectrum antibiotic, for the treatment of CD. The aim of this study was to evaluate the effect of rifaximin on the intestinal microbiota of four patients affected by active CD by using a three-stage in vitro continuous culture system designed and validated to reproduce spatial, temporal, nutritional, and physico-chemical characteristics of the microbiota in the proximal (vessel 1), transverse (vessel 2) and distal colon (vessel 3). Rifaximin was added in 3 times at a concentration of 1800 mg/day and the treatment was carried out for a period of 16 days. Most representative bacterial groups were evaluated by FISH and PCR-DGGE. Microbial metabolic profiles were analyzed using H1-NMR and SPME-GC/MS. Additionally, the potential cyto- and geno-toxic effects of the faecal water were evaluated by HT29 cells-growth assay and COMET assay. Our results demonstrated that rifaximin did not drastically modify the biostructure of the intestinal microbiota, and elicited an increase of Bifidobacterium concentration in the whole fermentative system and Atopobium cluster in the vessel 1. HT29 cells-growth assay demonstrated that faecal water containing rifaximin was not cytotoxic and exerted a cyto-protective role in Vessel 2. Additionally, COMET assay revealed that rifaximin was not genotoxic and could exert a chemopreventive role, by preventing the DNA damage induced from hydrogen peroxide in Vessel 2 and 3. Preliminary data from H1-NMR and SPME-GC/MS showed that some variations in microbial metabolic profile occurred after rifaximin treatment, especially in term of SCFA, carbon disulfide, propanol, 1-nonanone and 2-methyl hexanol.
S. Maccaferri, A. Costabile, B. Vitali, P. Brigidi, G. R. Gibson (2009). Rifaximin modulates the colonic microbiome and metabonome of Crohn Disease patients: an in vitro approach using a continuous culture gut model system. SPOLETO : SIMGBM.
Rifaximin modulates the colonic microbiome and metabonome of Crohn Disease patients: an in vitro approach using a continuous culture gut model system
MACCAFERRI, SIMONE;VITALI, BEATRICE;BRIGIDI, PATRIZIA;
2009
Abstract
Crohn’s disease (CD) is a chronic inflammatory condition of the gastrointestinal tract and its aetiology still remains unknown. In the last years, it has been shown the clinical efficacy of rifaximin, a poorly absorbed and broad-spectrum antibiotic, for the treatment of CD. The aim of this study was to evaluate the effect of rifaximin on the intestinal microbiota of four patients affected by active CD by using a three-stage in vitro continuous culture system designed and validated to reproduce spatial, temporal, nutritional, and physico-chemical characteristics of the microbiota in the proximal (vessel 1), transverse (vessel 2) and distal colon (vessel 3). Rifaximin was added in 3 times at a concentration of 1800 mg/day and the treatment was carried out for a period of 16 days. Most representative bacterial groups were evaluated by FISH and PCR-DGGE. Microbial metabolic profiles were analyzed using H1-NMR and SPME-GC/MS. Additionally, the potential cyto- and geno-toxic effects of the faecal water were evaluated by HT29 cells-growth assay and COMET assay. Our results demonstrated that rifaximin did not drastically modify the biostructure of the intestinal microbiota, and elicited an increase of Bifidobacterium concentration in the whole fermentative system and Atopobium cluster in the vessel 1. HT29 cells-growth assay demonstrated that faecal water containing rifaximin was not cytotoxic and exerted a cyto-protective role in Vessel 2. Additionally, COMET assay revealed that rifaximin was not genotoxic and could exert a chemopreventive role, by preventing the DNA damage induced from hydrogen peroxide in Vessel 2 and 3. Preliminary data from H1-NMR and SPME-GC/MS showed that some variations in microbial metabolic profile occurred after rifaximin treatment, especially in term of SCFA, carbon disulfide, propanol, 1-nonanone and 2-methyl hexanol.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
