Category Archives: Inflammatory bowel disease

Prebiotics for inflammatory bowel disease: Conclusions

A low intake of lactose was associated with a predominance of sulfomucin (a characteristic of colonic mucosa). In addition, there was also an inverse association with lactose intake and fecal aerobes. The authors concluded that the relationship between lactose intake and findings of mucin and fecal bacteria supports a possible prebiotic effect of lactose.  Conclusions drawn from the present review on the use of pre-biotics for IBD include the following. In general, proof of principle has been established that prebiotics work. Continue reading

Prebiotics for inflammatory bowel disease: Human studies (Part 4)

LactoseLactose, a potential prebiotic, also has not been demonstrated to have an impact in disease development when predisease diet history is considered. Perhaps disaccharides are not ideal prebiotics in patients with established IBD. They may be more beneficial in preventing early IBD. There are two papers published with the use of prebiotics for pouchitis. The first by Welters et al reported the only double-blind placebo-controlled study. The study consisted of 20 patients and compared placebo with 24 g of inulin per day in a crossover design. Continue reading

Prebiotics for inflammatory bowel disease: Human studies (Part 3)

The three-week intervention trial used 10 g of lactulose given twice daily and used the measurable instrument of colonic adaptation to the high-dose lactulose challenge to compare outcome in controls versus patients. Colonic adaptation is defined as diminished breath hydrogen and improved symptoms of sugar intolerance on repeat challenge after continued low-dose consumption of the specified sugar. The concept was based on the work of Flourie et al and the hypothesis of Liao et al. The results showed that while controls achieved significant reductions in measured breath hydrogen and symptoms, the combined group and, especially, the separated CD patients failed to adapt. Continue reading

Prebiotics for inflammatory bowel disease: Human studies (Part 2)

patients treated with GBFThere are three published open-label studies comprising a total of 49 patients treated with GBF for mild to moderately active UC in Japan. The first pilot study by Mitsuyama et al showed clinical improvement with GBF 30 g/day for four weeks. A follow-up study also for four weeks with 20 g to 30 g GBF per day using slightly larger numbers also showed clinical improvement and confirmed that bifidobacteria and eubacteria were increased in the stool. A more recent study by the same group extended treatment for 24 weeks and again showed clinical improvement. In all of these studies, patients were continued on standard 5-ASA or corticosteroid therapy and these were continued throughout the observation period. Continue reading

Prebiotics for inflammatory bowel disease: Human studies (Part 1)

To our knowledge there are nine published papers on the use of prebiotics in some form in IBD (Table 2). Two studies are with fibre that represent candidate prebiotics in an expanding definition from the original. The first of these studies evaluated 29 patients with UC in remission. Over a four-month period Hallert et al evaluated the effect of Ispaghula husks (Plantago ovata) against placebo while patients were maintained on standard therapy. There was a statistically significant quantity of symptomatic improvement in the intervention group (69% versus 24%). Continue reading

Prebiotics for inflammatory bowel disease: Animal studies (Part 2)

rats treated with GBFIn dextran sulfate sodium-challenged rats treated with GBF, both bifidobacteria and eubacteria were measurably increased and the total number of aerobes and bac-teroides were decreased. In addition to these effects, the glutamine-containing portion of GBF may also exert independent effects. Rats exposed to glutamine alone, before another agent (trinitrobenzene sulfonic acid [TNBS]), showed resistance to inflammation.

Prebiotics, much like individual species of probiotics, may exert specific effects on the type of colitis induced. Continue reading

Prebiotics for inflammatory bowel disease: Animal studies (Part 1)

Published studies to date on the use of prebiotics in IBD models have established proof of principle in animals (Table 1). Models used include the interleukin-10 knockout mouse that tends to reproduce a colitis resembling CD. Although the mice are normal at birth, by four weeks they develop a mild colitis which reaches a maximum severity by eight weeks. Madsen et al have published at least two relevant studies with this model. In the first report, orally administered lactulose or Lactobacillus reuteri by rectal enema were able to attenuate colitis. In the second study, breast milk from normal wild mice fed to interleukin-10-deficient mice also failed to develop colitis. Continue reading

Prebiotics for inflammatory bowel disease: Changes in microbial flora (Part 4)

colonic environmentSome other compounds such as resistant starch and other soluble fibres share some of the properties of prebiotics. Two major features of these nondigestible products are relevant to their impact on the colonic environment. Bacterial metabolism leads to physicochemical alterations that include decreased pH because of lactic acid and short chain fatty acid (SCFA) production (acetate propionate and butyrate). The specific bacteria, species of lactic acid-producing bacteria (LAB), metabolize prebiotics preferentially. Continue reading

Prebiotics for inflammatory bowel disease: Changes in microbial flora (Part 3)

In this context, two strategies have been used. First, the use of direct live probiotics has been tested. These bacteria have species-specific features that limit effects of other ‘harmful’ commensal species. Some of the described effects attributed to probiotic species in experimental conditions include stimulation of epithelial cell proliferation , enhancement of barrier function, prevention of pathogen epithelial adhesion , limitation on pathogen colony expansion and anticytokine effects. Secondly, favourable manipulation of the luminal environment can also be achieved with the use of specific dietary components. The paramount dietary substances for this purpose are prebiotics. Continue reading

Prebiotics for inflammatory bowel disease: Changes in microbial flora (Part 2)

microflora in the lower intestineAcquisition of specific and permanent microflora in the lower intestine begins very soon after birth and remains quite stable in healthy individuals until later in life. Protective bifidobacteria start to diminish in late middle age and Clostridium species begin to increase progressively around the same time. These bacterial changes are thought to be related to altered health and may promote diseases associated with aging (eg, colorectal cancer).

The changes observed with aging qualify for the definition of dysbiosis, “a breakdown in balance between putative species of protective versus harmful intestinal bacteria”. As such, this term has been applied to IBD as well (especially CD). Continue reading

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