IBS is a common disturbance of the bowel characterized by abdominal pain or discomfort alongside abdominal distention. It is commonly associated with gastroenteritis. In fact, a meta-analysis has found that there is a 3- to 11-fold higher risk of IBS after a gastroenteritis episode.
Post-infectious IBS (Pi-IBS) is a common disease where IBS symptoms begin after acute gastroenteritis. Pi-IBS accounts for up to 30 percent of patients with bacterial gastroenteritis and seems to be a nonspecific response to the infection.
Probiotics have already been used in the treatment of many functional gastrointestinal (GI) symptoms and syndromes. With this in mind, the researchers conducted a study to see whether probiotics could help reduce symptoms of Pi-IBS. (Related: Quercetin: A natural painkiller for people with IBS.)
To conduct their study, the researchers used the nematode Trichinella spiralis to induce IBS in mice. They used two sets of mice, one group infected with T. spiralis and the other group pathogen-free.
The mice were then randomly split into groups. The first group was given formulated probiotics (DW) composed of Lactobacillus acidophilus LA5 and Bifidobacterium animalis subsp. lactis BB12 and the yeast culture Saccharomyces cerevisiae var. boulardii.
The second was given probiotics (VSL#3) containing Streptococcus thermophilus, B. breve, B. longum subsp. longum, B. longum subsp. infantis, L. acidophilus, L. plantarum, L. paracasei and L. delbrueckii subsp. bulgaricus.
The third group was given a placebo and served as a control.
After weeks of being fed either probiotics or a placebo, the abdominal withdrawal reflex of the mice was measured.
The researchers also conducted quantitative reverse transcription polymerase chain reaction testing to study the effects of probiotics on target gene expression levels, specifically of protease-activated receptor-2 (PAR-2). The latter has been noted to cause the release of pro-inflammatory cytokines, making it important in the pathogenesis of organic and functional GI disorders.
In addition, the researchers looked at how the probiotics affected the expression of pro-inflammatory cytokines, such as TNF-?, IL-1 and IL-6. The levels of these have been found to be positively correlated with IBS symptoms in the blood cytokine profiles of IBS patients.
Over the course of their study, the researchers noted the reduction of Pi-IBS symptoms in the mice infected with T. spiralis after they were given probiotics. Specifically, they noticed that these mice experienced a change in the levels of pro-inflammatory cytokines.
In addition, they found that the DW group had significantly reduced levels of pro-inflammatory cytokines, IL-1 and IL-6.
Based on these results, the researchers concluded that formulated probiotics, specifically the DW formulation with L. acidophilus LA5, B. animalis subsp. lactis BB12 and S. cerevisiae var. boulardii, shows promise as a potential probiotic medication for patients with IBS and Pi-IBS.
In addition, the team noted that the outcome of their study shows a need for further research into probiotic strains and their impact on IBS symptoms.
For the latest studies on IBS and other GI diseases, visit Digestion.news.