Chemistry Reference
In-Depth Information
did not differ greatly between conditions. No significant improvement in clinical
activity index, endoscopic score, or immunohistochemical parameters was observed,
although UC sufferers did report a significant increase in quality of life. The absence
of a sole-lactulose treatment group prevented the determination of the prebiotic effect
in human IBD, and the failure to replicate the positive results observed
in vivo
could
have occurred as a result of a nonideal combination with medication. Despite the
effect of lactulose not being supported by the investigated parameters, the increase
in quality of life following administration reported by UC sufferers indicates further
investigation is warranted. UC appears to be suited to prebiotic treatment, with GBF
reducing disease severity both clinically and endoscopically as well as increasing the
concentration of fecal butyrate.
89
Another dietary fiber, derived from the
Plantago
ovate
seed, has also been demonstrated to have therapeutic effects. It has been shown
to increase fecal butyrate levels, and was as effective as conventional mesalamine
treatment to maintain remission in patients with UC in an open-label study of 102
patients.
90
FOS administration has yielded promising results in studies involving patients
with CD. Lindsay and colleagues reported increased fecal bifidobacteria concentra-
tions and a decrease in disease severity.
80
Interestingly, FOS also increased levels of
D C s e x p r e s s i n g T L R-2 a n d T L R- 4 , a s well l l a s I L -10
+
D C s . I m m u n o m o d u l a t o r y e f f e c t s
of prebiotics have not been studied extensively, but indicate another mechanism via
which they could be associated with efficacy in IBD treatment. Furthermore, com-
bination with probiotics that exert similar beneficial effects could increase potency
of the treatment. Hussey and colleagues reported efficacy of FOS administration,
although it was delivered in combination with inulin and whey protein.
91
Once
again, disease severity scores were reduced following treatment, as were erythro-
cyte sedimentation rates, a biochemical marker of inflammation. The effects of FOS
administration alone were not determined, but may have been useful in identifying
the most active component of the combination and, hence, potential methods of
increasing its potency.
Prebiotics have also demonstrated efficacy in the setting of pouchitis. Welters
and colleagues reported a decrease in both histological and endoscopy scores of
patients with pouchitis following inulin administration.
92
Inulin administration was
shown to reduce the concentration of
Bacteroides fragilis
, a bacteroide hypoth-
esized to initiate inflammation in pouchitis and associated with villous atrophy,
but had no effect on commensal lactobacilli or bifidobacteria concentrations. Fecal
butyrate levels were also increased by inulin administration, leading to increased
energy availability for colonic epithelial cells, which may have aided to tissue
repair and regeneration.
Prebiotics have demonstrated efficacy both in animal models
in vivo
and in clini-
cal trials. Similar to probiotics, a greater understanding of the role of the intestinal
microbiota in IBD is required in order to optimize their efficacy. This would facili-
tate the development of more effective microbial therapies as specific targets for
manipulation will be identified. In addition to exerting their own beneficial effects,
prebiotics could also be utilized to manipulate the microbiota to facilitate the sur-
vival of probiotic species or increase the efficacy of other therapeutics.
