Viruses gleaned from healthy feces fight obesity in mice

Altering the gut microbiome by transplanting the stool contents from a healthy donor is emerging as a promising way to treat a variety of conditions, including everything from autism to inflammatory bowel disease to cancer.

Scientists looking to this technique as a way of treating obesity have found some early success in mice, after implanting virus particles gleaned from the feces of lean mice curtailed weight gain and progression of a precursor of type 2 diabetes.

The work was carried out by scientists at the University of Copenhagen and focuses on a relatively new arm of fecal transplant science, where some contents of the stool are first separated from the others. Unlike typical fecal transplants where the stool in its entirety is administered to the patient, this technique first filters out the live bacteria from the sample, while upping the concentration of virus particles known as bacteriophages at the same time.

These viruses can alter the gut microbiome on their own by specifically targeting and attacking bacteria, and are themselves an area of intense focus for some scientists in the field. Previous research has shown how these predators can trigger a cascade of effects on the microbial communities in our bellies, while the technique could also avoid some of the risks of disease transmission that come with transplanting live bacteria.