On Feb. 9 as part of the Microbes and Social Equity Speaker Series, the University of Maine Institute of Medicine organized a seminar on diet, microbial metabolites and cancer disparities. Dr. Patricia Wolf, a registered dietitian nutritionist and postdoctoral fellow at the Cancer Education and Career Development Program NCI T32 at the University of Illinois at Chicago, spoke during this session.
Her research investigates microbial mechanisms of cancer health disparities related to inequitable food access and quality. The techniques in molecular microbiology and novel enzyme characterization helps Wolf to understand the metabolic capacity of the human gut microbiome. Her research looks at whether dietary intake shifts microbial ecology and function toward the formation of deleterious microbial metabolites which contribute to cancer risk. This is due to the fact that dietary behaviors are shaped by social and structural environments and will include works that explore relationships between the neighborhood food environment, and microbial metabolism in order to mitigate the inequitable burden of cancer in certain demographics.
“I know that dietary intake is often driven by the nutrition environment,” said Wolf. “And so I’m hoping in the future that I’ll be able to look at associations between nutrition environments and dietary intake and then impact policies and structures that shape these nutritional environments.”
Wolf proceeds to take the audience through her five step research method: identifying the association between microbial metabolites and disease, determining the functional capacity of the human microbiome, characterizing unknown microbial enzymes, determining association between diet and microbiome function and examining diet in context of the nutrition environment.
“Our work so far has focused mostly on colorectal cancer since it’s the third leading cause of cancer incidence and death in the US,” says Wolf. “Colorectal cancer incidence has actually decreased, and this is mostly due to the increase in screening colonoscopy. However, this decrease has been attenuated in certain groups, specifically non-Hispanic Black [people] who have the highest incidence of colorectal cancer in the United States … [W]e think that microbial metabolites could be the environmental trigger sparking this progression.”
Wolf further discusses the greater colorectal cancer incidence and mortality in Black Americans, as well as the hydrogen sulfide produced by bacteria in the gut. While the sulfate reducing bacteria has been well studied, bilophila wadsworthia has been gaining more traction in how it uses the amino acid Taurine through a multi step process to produce hydrogen sulfide. These two pathways, sulfate reducing bacteria and bilophila wadsworthia with Taurine, are important in relation to how they both share the last step in the production of hydrogen sulfide.
“We found that regardless of disease state, African American Black [people] actually had ten times higher concentrations of these microbes,” says Wolf.