Purpose: The pathogenesis of inflammatory bowel disease is thought to be a multifactorial process. One of the leading hypotheses is that an imbalance in normal gut flora induces an excessive immune response and contributes to inflammation in the gastrointestinal tract. Administration of probiotic bacteria reduces symptoms in patients suffering from inflammatory bowel diseases, probably via both manipulation of the microflora and stimulation of the intestinal immune system. In the current study the therapeutic potential of two different probiotics-Lactobacillus GG and a mixture of Streptococcus thermophilus, Lactobacillus acidophilus, and Bifidobacterium longum (YO-MIX Y 109 FRO 1000)--in a rat model of colitis were evaluated.
Methods: Male Wistar rats were administered probiotics for three days simultaneously with colitis induction. Colonic damage was evaluated histologically and biochemically and colonic tissues, as well as fecal samples, were used for bacterial studies using 16S rRNA gene primers.
Results: Probiotics administration reduced the relative amounts of the pathogenic bacteria Aeromonas and Escherichia coli in the colonic tissue. However, whereas both probiotics affected colon morphology, only Lactobacillus GG administration reduced myeloperoxidase activity.
Conclusions: We report the therapeutic rather than preventive potential of two different probiotics in an animal model of colitis.