Lactobacillus plantarum 299v (L. plantarum 299v) (DSM 9843) is a probiotic strain able to reside in the human colonic mucosa in vivo due to a specific mechanism of mannose adhesion. L. plantarum 299v (DSM 9843) also increases the amount of carboxylic acid, particularly acetic and propionic acids, in the stools of healthy volunteers. The strain has shown antibacterial activity against several potential pathogenic agents such asListeria monocytogenes, Escherischia coli, Yersinia enterolytica, Enterobacter cloacae and Enterococcus faecalis. L. plantarum 299v (DSM 9843) also has beneficial immunomodulatory activity via an increased interleukin-10 synthesis and secretion in macrophages and T-cells derived from the inflamed colon. And recently, an experimental study reported that L. plantarum 299v (DSM 9843) increased the transcription and excretion of the mucins MUC2 and MUC3 in goblet cells.
Participants (n = 214) were recruited by general practitioners in four clinical centres in India: one in Mumbai, two in Chennai and one in Bangalore. Subjects between 18-70 years of age with IBS according to the Rome III criteria were eligible for inclusion. All subjects had a colonic examination at baseline to exclude any organic disease while an intestinal infection was excluded by stool cultures in any patient in whom this diagnosis was suspected. Subjects with severe chronic medical disease including colorectal and other gastrointestinal diseases were excluded. Pregnant and breast-feeding women and patients with dietary habits which might interfere with the assessment of the study product or patients with known allergy to the study product components were also excluded. Throughout the study, the subjects were not allowed to consume any other probiotic and were encouraged not to change their usual dietary and physical exercise habits.
This study was designed as a multicentre double blind, placebo-controlled study with parallel groups to assess the beneficial effects of a daily consumption of L. plantarum 299v (DSM 9843) on IBS symptoms. Treatment duration was 4 wk with 3 follow-up visits at weekly intervals. The study protocol was conducted in accordance with the Declaration of Helsinki and approved by the local Ethics Committee. All volunteers gave written informed consent prior to participation in the study.
The test product was a probiotic preparation containing a mixture of freeze-dried lactic acid bacteria and excipients. The lactic acid bacteria strain was L. plantarum 299v (DSM 9843). It is deposited at the DSM collection (Deutsche Sammlung von Mikrooorganismen und Zellkulturen GmbH) under number DSM 9843. The test product contained 10 billion colony-forming units (cfu) per capsule in a potato starch and magnesium stearate base. The control product contained potato starch (97%) and magnesium stearate (3%). Both the test and control products had a similar appearance, texture and taste. Both products were specifically prepared for the study and provided by the Rosell-Lallemand Institute (Blagnac, France).
The present study shows the potential benefit of a particular strain L. plantarum 299v (DSM 9843), in the management of IBS. Further studies are warranted in order to identify the mechanism of the probiotic’s potential beneficial effect.