Think about the last thing that you ate. Ever wondered how the body converts the food you eat into the energy needed to sustain its constant biological processes? The truth is that your body doesn’t do it alone; it’s assisted by billions of microscopic helping hands, a grand collection of bacteria, fungi, viruses, and other tiny beasties that live within our stomach and intestines, called our gut microbiome. Since we can’t readily absorb nutrients from many of the foods we eat, the gut microbiome helps to metabolize, or break down, our foods into vitamins and smaller molecules that our cells can use. In recent decades, we’ve come to understand just how powerful an influence the gut microbiome has on our overall health.

This month, a study published in Cell investigated the gut’s influence on cardiovascular disease, one of the leading causes of death in the United States. Researchers used stool and plasma samples collected from over 1400 participants, which serve as a snapshot of what microbes are present in the gut and what they’re digesting at any given time. Most interestingly, they found that a group of bacteria called Oscillibacter was highly correlated with greater numbers of cholesterol byproducts, or metabolites, in plasma, hinting that this previously un-investigated microbe was potentially responsible for breaking down harmful cholesterol. To validate this suspicion, they performed laboratory experiments where they cultured the bacteria and added cholesterol. Results showed that several species of Oscillibacter were capable of efficiently metabolizing cholesterol.

From these experiments, it is clear that Oscillibacter has some untapped potential as an aid in combating cardiovascular disease. A major goal of microbiome research is to find actionable ways to improve human health. With more insight into the gut microbiome’s role, we can look towards a future where we discover and harness similar members of this powerful internal ecosystem to prevent a variety of diseases.

This study was led by postdoctoral research fellow Chenhao Li at the Broad Institute of MIT and Harvard, with corresponding author Ramnik J. Xavier.

Managing Correspondent: Maati McKinney

Press Article: Gut bacteria break down cholesterol — hinting at probiotic treatments (Nature News)

Original Journal Article: Gut microbiome and metabolome profiling in Framingham heart study reveals cholesterol-metabolizing bacteria (Cell)

Image Credit: NIH Image Gallery on Flickr/Darryl Leja, National Human Genome Research Institute, National Institutes of Health