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Manipulation of Visceral Hypersensitivity With Probiotic Bacteria in Irritable Bowel Syndrome

This study has been completed.
Information provided by:
Chinese University of Hong Kong Identifier:
First received: June 3, 2010
Last updated: January 18, 2013
Last verified: February 2011
Irritable bowel syndrome is a common digestive disorder worldwide. However, there is no effective treatment of irritable bowel syndrome. Visceral pain thresholds in response to stress are lower in patients with IBS compared to healthy volunteers, but the triggers to visceral hypersensitivity remain largely unknown. Animal models suggest roles for both host immune response and intestinal bacteria in the induction of visceral hypersensitivity. For instance colorectal distension increased in association with an alteration in bacterial flora induced by antibiotic therapy, which suggest a relationship between bacterial gut content and visceral afferent processing. Intestinal bacteria play a significant role in inducing IBS. Clinical studies have shown that manipulation of the commensal microbiota with probiotic bacteria, in particularly preparations that contain bifidobacteria, can alleviate IBS symptoms. Serotonin (5-HT) plays a crucial role in the regulation of gastrointestinal physiology and alterations in mucosal serotonin signaling is a possible mechanism of altered function and sensation in patients with IBS. Impairment of serotonin reuptake transporter (SERT) expression and function may also play a role in IBS. The investigators hypothesise that bacteria modulate sensory afferent and serotonin signaling necessary for visceral sensation and that these pathways can be targeted for therapy of IBS using probiotic bacteria. The first part of this study will be a cross-sectional study comparing the colonic microbiota and SERT polymorphisms in IBS patients and healthy controls. The second part will be an open-label pilot study to assess the effects of oral probiotic bacteria in visceral hypersensitivity and mucosal microbiota in patients with IBS. Clinical response will be assessed based on IBS symptom score and rectal sensitivity, and changes in mucosa microbiota will be measured using 454 pyrosequencing. This proposal will provide novel data on gut microbiota in Asian IBS patients, and explore the mechanisms underlying visceral hypersensitivity to direct future targeting of therapy in IBS.

Condition Intervention Phase
Irritable Bowel Syndrome
Dietary Supplement: VSL#3
Phase 4

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Manipulation of Visceral Hypersensitivity With Probiotic Bacteria in Irritable Bowel Syndrome

Resource links provided by NLM:

Further study details as provided by Chinese University of Hong Kong:

Primary Outcome Measures:
  • Clinical symptoms [ Time Frame: 4 weeks post probiotic ]

Secondary Outcome Measures:
  • Differences in gut microbiota between IBS patients and controls [ Time Frame: 1 year ]
  • Difference in gut microbiota post probiotic in IBS patients [ Time Frame: 1 year ]
  • Differences in blood and mucosal SERT polymorphisms between IBS patients and controls [ Time Frame: 1 year ]
  • Rectal sensitivity [ Time Frame: 4 weeks post probiotics ]

Enrollment: 12
Study Start Date: July 2010
Study Completion Date: March 2011
Primary Completion Date: March 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Probiotics
IBS Patients will receive VSL#3 (450 billion lyophilized bacteria/sachet) twice daily for 4 weeks. VSL#3 was selected for use in this study because (a) it contains three different Bifidobacteria strains (in addition to lactobacilli and streptococci) and the limited evidence available Bifidobacteria as the most effective probiotics in IBS .
Dietary Supplement: VSL#3
IBS Patients will receive VSL#3 (450 billion lyophilized bacteria/sachet) twice daily for 4 weeks

  Show Detailed Description


Ages Eligible for Study:   18 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

Symptoms of abdominal pain or discomfort of at least 3 times a month, in the last 6 months, associated with 2 or more of the following:

  • Improvement with defecation
  • Onset associated with a change in frequency of stool
  • Onset associated with a change in form (appearance) of stool

Exclusion Criteria:

  • history of weight loss or rectal bleeding
  • history of psychiatric illness (severe depression, mania and schizophrenia)
  • history of active infection
  • recent antibiotic therapy or anti-inflammatory medication
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01139736

Hong Kong
Prince of Wales Hospital
Shatin, Hong Kong
Sponsors and Collaborators
Chinese University of Hong Kong
Principal Investigator: Siew C Ng, PhD Chinese University of Hong Kong
  More Information

Additional Information:
Responsible Party: Dr Siew C Ng, The Chinese Unviersity of Hong Kong Identifier: NCT01139736     History of Changes
Other Study ID Numbers: IBS Probiotics
Study First Received: June 3, 2010
Last Updated: January 18, 2013

Keywords provided by Chinese University of Hong Kong:
Irritable bowel syndrome
rectal sensitivity
gut flora
gut bacteria

Additional relevant MeSH terms:
Irritable Bowel Syndrome
Pathologic Processes
Colonic Diseases, Functional
Colonic Diseases
Intestinal Diseases
Gastrointestinal Diseases
Digestive System Diseases
Immune System Diseases processed this record on May 22, 2017