Effects of Probiotic Formulations

Probiotics are ingestible microorganisms having health benefit beyond their intrinsic nutritive value. Probiotics have been used to treat a variety of gastrointestinal ailments including inflammatory bowel disease, rotavirus and antibiotic-associated diarrhea, to name a few. They appear to have protective, trophic and anti-inflammatory effects on bowel mucosa. However, the exact mechanisms by which probiotics act to protect against mucosal injury have yet to be fully elucidated.

Activation of the NF-kB pathway is thought to be a key molecular event involved in the pathogenesis of many conditions of intestinal inflammation. We have shown that certain probiotics inhibit the NF-kB pro-inflammatory pathway, which may account for some of their anti-inflammatory effects. In addition, we have demonstrated that probiotics induce the expression of certain cytoprotective heat shock proteins (HSPs) which belong to a family of highly conserved proteins and play an important role in protecting cells against physiologic and pathogenic stressors in the environment. In intestinal epithelial cells, these inducible HSPs convey a degree of cytoprotection, prolong viability under conditions of stress and preserve the integrity of intestinal epithelial cell barrier function under hostile conditions. Efforts are currently underway to more fully characterize the microbial-epithelial cell interactions involved and to isolate the probiotic bioactive factor(s) responsible for these effects.

Other Studies

Bench laboratory studies are also part of the clinical studies of immune reconstitution in HIV and epidemiology of VRE on the transplant units described under Clinical Research.

Future Directions

There is a joint recruitment underway by the Section of Infectious Diseases and the Committee on Microbiology to identify a Clinical Scientist with a basic laboratory program. The Department of Medicine has committed to this position in order to strengthen the basic science activities of the section.