Effects of Bifidobacterium longum BB536 and Lactobacillus rhamnosus HN001 in IBS patients.

BACKGROUND: Irritable bowel syndrome (IBS) is a common gastrointestinal disorder, which still lacks effective therapy. We aimed to investigate the effects of a novel formulation of Bifidobacterium longum BB536 and Lactobacillus rhamnosus HN001 with vitamin B6 (LBB) on symptoms, intestinal permeability, cultivable bacteria and metabolome in IBS subjects. MATERIALS AND METHODS: Twenty-five IBS patients (Rome IV criteria) (M:F = 8:17; age 48 years ± 11 SD) were randomized to treatment (LBB) or placebo (one month each) in a crossover randomized double-blind controlled trial. Symptoms, intestinal habits, disease severity, intestinal permeability and intestinal microbiota were analysed at 0, 30, 45 and 60 days. RESULTS: Percentage decrease from baseline of abdominal pain (-48.8% vs -3.5%), bloating (-36.35% vs +7.35%) and severity of disease (-30.1% vs -0.4%) was significantly (P < .0001) greater with LBB than placebo, respectively. In IBS-D patients, the improvement from baseline of Bristol score was more consistent with LBB (from 6 ± 0.4 to 4.3 ± 1.1, P < .00001) than placebo (from 6.2 ± 0.7 to 5.3 ± 1.1, P = .04). In IBS-C patients, Bristol score tended to improve from baseline after LBB (2.6 ± 1.1 vs 3.2 ± 0.5, P = .06). LBB significantly improved the percentage of sucralose recovery (colonic permeability) (1.86 ± 0.1 vs 1.1 ± 0.2, P = .01). During treatment, presumptive lactic acid bacteria and bifidobacteria, relative abundance of propanoic, butanoic, pentanoic acids and hydrocarbons increased, while phenol decreased. CONCLUSIONS: The novel formulation of B. longum BB536 and L. rhamnosus HN001 with B6 vitamin improves symptoms and severity of disease, restores intestinal permeability and gut microbiota in IBS patients.

The Role of Dietary Approach in Irritable Bowel Syndrome.

Irritable bowel syndrome (IBS) is a chronic functional disorder of the gastrointestinal tract and is one of the most frequent gastrointestinal diseases. In IBS multiple pathophysiological mechanisms including alterations in intestinal motility, permeability, nutrient absorption, and intestinal microbiota have been implicated. Foods are commonly reported by patients to be a trigger of symptoms and therefore are likely involved in the generation of symptoms in IBS. Among all possible therapeutic options, a first-line approach to IBS is dietary education and identification of foods potentially responsible for the onset or worsening of symptoms. Dietary approaches include reduction of gas-producing foods (i.e. fermentable oligo-, di-, and monosaccharides and polyols (FODMAPs)), lactose and gluten. Further studies are required to link the ultimate role of diets in different IBS subtypes.