Washington: Researchers have shown that when chitosan - used in agriculture as a seed treatment and biopesticide - is given in conjunction with antibiotics, it assists the bladder in ridding itself of "reservoir" populations of bacteria that live in its deeper layers and potentially cause recurrent infections.
If the effectiveness of chitosan against reservoir populations of bacteria could be confirmed in people, the compound might one day serve to augment antibiotic treatments of recurrent UTIs, according to Matthew Blango, Ph.D., a U of U postdoctoral researcher and first author on the study.
Matthew Mulvey, Ph.D., U of U professor of pathology senior author on the study. Elizabeth M. Ott, Ph.D., also a U postdoctoral fellow, is a co-author along with two researchers from the University of Ljubljana, Slovenia.
To destroy reservoir populations of UPEC, Blango, Mulvey and their colleagues infused mouse bladders with chitosan for 20 minutes, during which time the compound worked to exfoliate large cells lining the surface of the bladders. The exfoliation of cells did not harm the deeper layers of the mouse bladders but caused dormant reservoirs of UPEC to move toward the surface of the bladders and divide and replicate, making them susceptible to antibiotics.
The researchers followed up the chitosan by giving the mice a one-week course of fluoroquinolones, an antibiotic class commonly used to treat UTIs. A week later, when they checked the level of UPEC in the mouse bladders, Blango and his colleagues found the reservoir populations of the bacteria for the most part were gone.
"Effectively, there were no bacteria in the bladder," Blango says.
The mouse bladders also regenerated the surface lining of exfoliated cells in about a week.
The study has been published online in the journal PLOS ONE.
