Millions of beneficial bacteria living in the human gut may actually be helping to protect the lining of the intestines. As a result, the practice of giving antibiotics to cancer patients to prevent infections might render the gut more vulnerable to damage, according to researchers.
This danger might be overcome by administering substances that mimic the protective presence of gut bacteria. The findings may also revise thinking about the treatment of inflammatory bowel disease (IBD), in which the intestine is believed to mount an inflammatory response to benign, or commensal, bacteria.
Until now, almost everything that has been known about the benefits of commensal bacteria had to do with their biological activity:
- Metabolizing nutrients to enable you to absorb them more readily
- Assisting in the early development of the gastrointestinal system
- Producing factors that prevent colonization by pathogenic bacteria
The study found beneficial bacteria trigger proteins called Toll-like receptors (TLRs) maintain the health of intestinal epithelial cells and activate machinery that responds to injury.
Previously, TLRs were thought to function strictly as assassins, recognizing molecules on the surface of pathogenic bacteria and triggering the innate immune system to attack. The predominant view was that TLRs were somehow prevented from recognizing commensal bacteria, yet unleashed specifically against pathogenic microbes.
Medical News Today July 23, 2004