Obesity increases the risk of a person suffering from Type 2 diabetes and other disorders. Researchers at the University of Copenhagen have shown that viruses from poo might be helpful to individuals affected.
In the new study, scientists were able to drastically reduce weight gain and prevent Type 2 diabetes in obese mice using viruses from the feces of their healthier counterparts. They made use of bacteriophages, which are viruses that constitute a threat to bacteria rather than to humans.
The study, which was sponsored by the Danish Council for Independent Research, showed effects of the treatment after at least six weeks. Its findings appeared in the journal Gut.
Feces for treatment
This study was not the first to show the potential of poo for the treatment of disorders.
Fecal transplants are increasingly being used for the treatment of certain types of patients. They are particularly employed for combating Clostridioides difficile, a bacterium that causes a severe form of diarrhea in humans.
This form of transplantation is also known as a fecal microbiota transplant. It involves moving some microorganisms from the gut of a healthy donor to the gut of a sick person.
Scientists studied what effects this type of transplants can have on obese mice in this research.
They used a technique called Fecal Virome Transplantation. This focuses specifically on using viruses for treatment.
Fecal transplants in obese mice
The Danish researchers obtained feces of lean mice that were fed a standard diet with a low amount of fat. They filtered these materials to derive virus particles, which were transplanted into mice on a high-fat diet using a tube.
The latter group of animals had been on high-fat diets for six weeks before the transplantation. They maintained the diet for an additional six weeks before being examined by the scientists.
The team observed that the obese mice showed significantly reduced weight gain after receiving the viral transplants. This was in comparison to animals that did not receive the same.
In addition, the treatment proved helpful for reducing the risk of glucose intolerance characteristic of Type 2 diabetes. Experiments revealed that animals on high-fat diets reacted to a glucose injection the same way those on low-fat diets did.
Type 2 diabetes normally reduces the ability of the body to absorb and use sugar in diet well.
Scientists believe that obesity and glucose intolerance are both results of imbalances in the gut microbiota. The amount and makeup of viruses in the gastrointestinal (GI) tract have been found to play a major role in maintaining balance.
“In the obese mice on high fat diet, that didn’t receive the virus transplant, we observed decreased glucose tolerance, which is a precursor of diabetes,” said the study’s first author Torben Sølbeck Rasmussen, a Ph.D. student. “Thus, we have influenced the gut microbiome in such a way that the mice with unhealthy lifestyles do not develop some of the common diseases triggered by poor diet.”
The approach will need to be combined with dietary changes, the researchers said. It will also not be recommended for all obesity cases, but only for the more severe conditions.
Senior study author Dennis Sandris Nielsen of the Department of Food Science at the University of Copenhagen said a long-term poor diet leads to gut imbalance. The Professor with Special Responsibilities (MSO) stated that their findings show balance can be restored by “shooting missing virus particles back into the system.”
No bacteria for transplantation
The research team took care to emphasize that this method uses only viruses in feces and no bacteria for transplants. This is a departure from the approach that has gained ground in recent years.
Poo is often transplanted without filtering out bacteria. The idea behind this is that gut bacteria are most potent for treatment. However, this has led to an accidental transmission of diseases in some cases – even to death.
“Our study demonstrates that there is an effect after the live bacteria have been filtered from stool,” Sandris Nielsen said. “Therefore, primarily virus particles are transmitted. This makes the method safer.”
The scientists said the mice study was the first step. According to them, their findings suggest that testing the method in humans will be worthwhile and that comes next. They hope further trials would lead to the identification of more potent, safer bacteriophages.
However, the scientists think it would take several years before the method would become available to patients.