Akkermansia muciniphila loves to degrade mucin, a molecule found in mucus. We’ve identified this and other mucus-degrading bacteria of our gut microbiome as playing a role in various human diseases such as inflammatory bowel disease, colitis, and colonic epithelial carcinogenesis. New research suggests this microbe plays a role in a deadly cancer treatment complication.
Neutrophils are an abundant and infection-fighting form of a white blood cell. Having low neutrophil levels is called Neutropenia. Cancer therapies, especially chemotherapy and bone marrow or stem cell transplantation, irradicate neutrophils along with cancer cells. The subsequent infections and neutropenic fevers in these patients have a 10% mortality rate.
One ongoing question in cancer research is, ‘Why do only half of neutropenia cancer patients develop a fever?’
In part, because infections in these patients often originate from the gastrointestinal tract, Schwabkey et al. at MD Anderson Cancer Center in Houston investigated how the gut microbiome could contribute to neutropenic fever. Using human samples and a mouse model, they discovered fever development was associated with the composition of intestinal bacteria.
Which brings us back to Akkermansia. Cytotoxic therapies such as radiation and chemotherapy caused an increase in Akkermansia bacteria. These mucous-eating microbes caused thinning of the intestine’s mucus layer and were associated with fever in human neutropenic patients.
The research identified a number of contributing factors that help Akkermansia thrive, such as calorie striction, inflammation, metabolic changes of the colon, pH, as well as low levels of the precursor in lipid creation and bacterial metabolite propionate.
This finding complements previous work from the University of Minnesota’s Staley laboratory which found the loss of protective metabolites in the gut was a contributing factor in neutropenic fever. This group, however, did not highlight propionate as one of their 18 recognized metabolites.
Schwabkey et al. identified the antibiotics of choice for suppressing Akkermansia. Azithromycin and tetracycline might offer protection for patients undergoing cytotoxic cancer therapies.
A thick, strong mucus-layered intestine can help prevent a major complication in cancer therapy. Finding more ways to fight these mucus-degrading bacteria using diet, monitoring colonic metabolite composition, pH, and antibiotic strategies could help keep cancer patients’ guts and temperatures in a healthy state.
Amielle Moreno earned her doctorate in neuroscience from Emory University and has dedicated her career to science communication, news coverage, and academic writing/editing. She is a published researcher who has branched out to author articles for various science websites. She recently published an original research article detailing her findings on how sensory areas of the brain respond to social sound. When she's not writing or editing, you can find her spinning the latest neuroscience news into comedy gold, hosting her podcast "Miss Behavior Journal Club." This fortnightly humorous podcast features the latest in behavioral research. Her goal in life is to defend and discover scientific truths.
