Rousseaux C, Thuru X, Gelot A, et al. Lactobacillus acidophilus modulates intestinal pain and induces opioid and cannabinoid receptors. Nat Med 2007;13:35-37.

Abdominal pain is common in the general population and, in patients with irritable bowel syndrome, is attributed to visceral hypersensitivity.

We found that oral administration of specific Lactobacillus strains induced the expression of μ-opioid and cannabinoid receptors in intestinal epithelial cells, and mediated analgesic functions in the gut—similar to the effects of morphine.

These results suggest that the microbiology of the intestinal tract influences our visceral perception, and suggest new approaches for the treament of abdominal pain and irritable bowel syndrome.

Bai A, Ouyang Q. Probiotics and inflammatory bowel diseases. Postgrad Med J 2006;82:376–382.

Enteric microflora profiles vary considerably between active inflammatory bowel diseases (IBD) and healthy conditions. Intestinal microflora may partake in the pathogenesis of IBD by one or some ways: specific pathogenic infection induces abnormal intestinal mucosal inflammation; aberrant microflora components trigger the onset of IBD; abnormal host immune response loses normal immune tolerance to luminal components; luminal antigens permeate through the defective mucosal barrier into mucosal lamina propria and induce abnormal inflammatory response.

Preliminary studies suggest that administration of probiotics may be benefit for experimental colitis and clinical trials for IBD. Researchers have been studying the function of probiotics.

Introduction of probiotics can balance the aberrant enteric microflora in IBD patients, and reinforce the various lines of intestinal defence by inhibiting microbial pathogens growth, increasing intestinal epithelial tight junction and permeability, modulating immune response of intestinal epithelia and mucosal immune cells, secreting antimicrobial products, decomposing luminal pathogenic antigens.

Williams E, Stimpson J, Wang D, et al. Clinical trial: a multistrain probiotic preparation significantly reduces symptoms of irritable bowel syndrome in a double-blind placebo-controlled study. Aliment Pharmacol Ther 2009;29(1):97-103.

Background

The efficacy of probiotics in alleviating the symptoms of irritable bowel syndrome (IBS) appears to be both strain- and dose-related.

Aim

To investigate the effect of LAB4, a multistrain probiotic preparation on symptoms of IBS. This probiotic preparation has not previously been assessed in IBS.

Methods

Fifty-two participants with IBS, as defined by the Rome II criteria, participated in this double blind, randomized, placebo-controlled study. Participants were randomized to receive either a probiotic preparation comprising two strains of Lactobacillus acidophilus CUL60 (NCIMB 30157) and CUL21 (NCIMB 30156), Bifidobacterium lactis CUL34 (NCIMB 30172) and Bifidobacterium bifidum CUL20 (NCIMB 30153) at a total of 2.5 × 1010 cfu/capsule or a placebo for 8 weeks.

Participants reported their IBS symptoms using a questionnaire fortnightly during the intervention and at 2 weeks post-intervention.

Results

A significantly greater improvement in the Symptom Severity Score of IBS and in scores for quality of life, days with pain and satisfaction with bowel habit was observed over the 8-week intervention period in the volunteers receiving the probiotic preparation than in the placebo group.

 Conclusion 

LAB4 multistrain probiotic supplement may benefit subjects with IBS.

Agrawal A, Houghton L, Morris J, et al. Clinical trial: the effects of a fermented milk product containing Bifidobacterium lactis DN-173 010 on abdominal distension and gastrointestinal transit in irritable bowel syndrome with constipation.  Aliment Pharmacol Ther 2008:29;104–114.

SUMMARY

Background

A sensation of abdominal swelling (bloating) and actual increase in girth (distension) are troublesome features of irritable bowel syndrome (IBS),which is more common in patients with constipation, especially those with delayed transit.

Aim

To establish whether a fermented dairy product containing Bifidobacterium lactis DN-173 010 reduces distension in association with acceleration of gastrointestinal transit and improvement of symptoms in IBS with constipation.

Methods

A single centre, randomized, double-blind, controlled, parallel group study in which patients consumed the test product or control product for 4 weeks. Distension, orocaecal and colonic transit and IBS symptoms were assessed on an intention-to-treat population of 34 patients.

Results

Compared with control product, the test product resulted in a significant reduction in the percentage change in maximal distension [median difference –39%, 95% CI (-78,-5); P = 0.02] and a trend towards reduced mean distension during the day [-1.52 cm (-3.33, 0.39); P = 0.096]. An acceleration of orocaecal [-1.2 h (-2.3,0); P = 0.049] as well as colonic [-12.2 h (-22.8,1.6); P = 0.026] transit was observed and overall symptom severity [-0.5(-1.0, -0.05); P = 0.032] also improved.

Conclusions

This probiotic resulted in improvements in objectively measured abdominal girth and gastrointestinal transit, as well as reduced symptomatology. These data support the concept that accelerating transit is a useful strategy for treating distension

McFarland LV, Dublin S. Meta-analysis of probiotics for the treatment of irritable bowel syndrome. World J Gastroenterol. 2008;14(17):2650-2661. Review.

Irritable bowel syndrome (IBS) is a chronic condition affecting 3%-25% of the general population. As no curative treatment is available, therapy is aimed at reducing symptoms, often with little success. Because alteration of the normal intestinal microflora has been observed in IBS, probiotics (beneficial microbes taken to improve health) may be useful in reducing symptoms.

This paper systematically reviews randomized, controlled, blinded trials of probiotics for the treatment of IBS and synthesizes data on efficacy across trials of adequate quality. PubMed, Medline, Google Scholar, NIH registry of clinical trials, metaRegister, and the Cochrane Central Register of Controlled Trials were searched from 1982-2007. We also conducted secondary searches of reference lists, reviews, commentaries, relevant articles on associated diseases, books and meeting abstracts.

Twenty trials with 23 probiotic treatment arms and a total of 1404 subjects met inclusion criteria. Probiotic use was associated with improvement in global IBS symptoms compared to placebo [pooled relative risk (RR pooled) 0.77, 95% confidence interval (95% CI) 0.62-0.94]. Probiotics were also associated with less abdominal pain compared to placebo [RR pooled = 0.78 (0.69-0.88)]. Too few studies reported data on other IBS symptoms or on specific probiotic strains to allow estimation of a pooled RR.

While our analyses suggest that probiotic use may be associated with improvement in IBS symptoms compared to placebo, these results should be interpreted with caution, given the methodological limitations of contributing studies. Probiotics warrant further study as a potential therapy for IBS.

PMID: 18461650

Ringel Y, Ringel-Kulka T, Maier D, et al. Probiotic Bacteria: Probiotic Bacteria Lactobacillus acidophilus NCFMand Bifidobacterium lactis Bi-07 Versus Placebo for the Symptoms of Bloating in Patients With Functional Bowel Disorders-a Double-blind Study. J Clin Gastroenterol 2011;45(6):518-525.

BACKGROUND:

Recent data suggest a role for the intestinal microbiota in the pathogenesis of functional bowel disorders (FBDs). Probiotic studies in FBDs generated inconsistent results suggesting a strain-specific and product-specific effect.

AIM:

To investigate the clinical efficacy of Lactobacillus acidophilus NCFM (L-NCFM) and Bifidobacterium lactis Bi-07 (B-LBi07) in nonconstipation FBDs.

METHODS:

A double-blind, placebo-control clinical trial of the probiotic bacterias L-NCFM and B-LBi07 twice a day (2 x 10¹¹ CFU/d) versus placebo over 8 weeks. Primary endpoints were global relief of gastrointestinal symptoms and satisfaction with treatment. Secondary endpoints were change in symptoms severity, well-being, and quality of life. Microbiological effect was assessed by quantitative real time polymerase chain reaction on fecal samples.

RESULTS:

Sixty patients (probiotic, n=31; placebo, n=29), 72% females, 84% whites, mean age 37 years. Abdominal bloating improved in the probiotics compared with the placebo group at 4 weeks (4.10 vs 6.17, P=0.009; change in bloating severity P=0.02) and 8 weeks (4.26 vs 5.84, P=0.06; change in bloating severity P<0.01). Analyses on the irritable bowel syndrome subgroup (n=33) showed similar results.

CONCLUSIONS:

L-NCFM and B-LBi07 twice a day improve symptoms of bloating in patients with FBDs. These data supports the role of intestinal bacteria in the pathophysiology of FBD and the role for probiotic bacteria in the management of these disorders.

PMID: 21436726

Kajander K, et al. A probiotic mixture alleviates symptoms in irritable bowel syndrome patients: a controlled 6-month intervention. Aliment Pharmacol Ther. 2005 Sep 1;22(5):387-394.

BACKGROUND: Irritable bowel syndrome is a gastrointestinal disorder of unknown aetiology. The effect of probiotics in this syndrome remains unclear.

AIM: To investigate whether a probiotic mixture containing Lactobacillus rhamnosus GG, L. rhamnosus LC705, Bifidobacterium breve Bb99 and Propionibacterium freudenreichii ssp. shermanii JS is effective in alleviating irritable bowel syndrome symptoms.

METHODS: A total of 103 patients fulfilling the Rome I or II criteria took part in this 6-month, randomized, double-blind placebo-controlled trial. The patients received a probiotic capsule or a placebo capsule daily. Gastrointestinal symptoms and bowel habits were recorded.

RESULTS: At the end the total symptom score (abdominal pain + distension + flatulence + borborygmi) was 7.7 (95% CI: -13.9 to -1.6) points lower in the probiotic group (P = 0.015). This represents a median reduction of 42% in the symptom score of the probiotic group compared with 6% in the placebo group. In individual symptoms, borborygmi was milder in the probiotic group (P = 0.008), and for the rest of the symptoms there was a non-significant trend.

CONCLUSIONS: The results indicate that this probiotic mixture is effective in alleviating irritable bowel syndrome symptoms. Considering the high prevalence of irritable bowel syndrome and the lack of effective therapies, even a slight reduction in symptoms could have positive public health consequences.

PMID: 16128676