Study author Matthew Redinbo is professor of chemistry at UNC-Chapel Hill College of Arts & Sciences, professor of biochemistry and biophysics and microbiology and immunology at UNC School of Medicine, and member of the UNC Lineberger Comprehensive Cancer Center.
New study in mice demonstrates precisely how triclosan, an antimicrobial found in toothpaste, toys and thousands of other products, can trigger intestinal inflammation.
An international team of researchers led by the University of North Carolina at Chapel Hill, the University of Massachusetts Amherst and the Baptist University of Hong Kong have identified the bacteria, and even specific enzymes, that trigger the harmful effects of triclosan. What’s more, studies in mice suggest that these bacterial enzymes may be prevented from causing intestinal damage.
The results were published in Nature Communication.
“By identifying the culprit bacteria, new approaches could be developed for the diagnosis, prevention and treatment of inflammatory bowel disease,” said the study author. Matthew Redinbo, professor of chemistry and microbiology at UNC-Chapel Hill College of Arts & Sciences and UNC School of Medicine.
Previous research has shown the toxicity of triclosan, but the new study takes a closer look at changes caused in the microscopic population of the gut.
The researchers connected specific gut microbial enzymes, including gut microbial beta-glucuronidase (GUS) proteins, with triclosan and showed that these enzymes lead triclosan to wreak havoc in the gut.
Knowing which bacterial proteins were the culprits, the team used a microbiome-targeted inhibitor to block the processing of triclosan in the gut. Blocking this process in mice helped prevent colon damage and symptoms of colitis, a form of inflammatory bowel disease.
The study provides new insights into the management of IBD in the growing number of people diagnosed with the disease. IBD can be managed for long periods of time only to appear out of nowhere.
The study’s authors suggest the need to better understand the impact of environmental chemicals on gut health.
Triclosan was once widely available in antibacterial soaps marketed to consumers. But in 2016, the Food and Drug Administration ordered it to be removed from hand washing products used in homes and hospitals over concerns that it was contributing to more resistant bacteria.
But triclosan remains ubiquitous as an ingredient added to cosmetics, yoga mats, and other clothing and sports equipment to reduce bacterial contamination. It’s also commonly used in many toothpastes – with FDA approval – because it’s been shown to prevent gingivitis.
Triclosan appears to be readily absorbed from the gastrointestinal tract.
The National Institutes of Health, through grants from several authors, the Hong Kong Research Grants Council and the National Science Foundation, funded the study “Microbial enzymes induce colitis by reactivating triclosan in the gastrointestinal tract of the mouse ”.