Fiber medicine

Fecal graft and fiber successfully treat metabolic syndrome

A clinical trial testing fecal transplants in severely obese subjects with metabolic syndrome found that the treatment was only beneficial when accompanied by non-fermentable fiber supplements. The phase 2 trial saw improvements in insulin sensitivity six weeks after a single fecal transplant.

We know that our gut bacteria influence our overall health, but the big challenge facing researchers right now is finding a way to turn this knowledge into therapeutic treatments for disease. Perhaps the simplest method is simply to take fecal samples from a healthy person and administer them to an unhealthy person.

Known as fecal microbial transplantation (FMT), this method is pretty much what you would imagine. A donor’s stool is screened for dangerous bacterial organisms, then prepared into capsules that are taken by mouth (or sometimes mixed with saline and administered through the other end). The goal is to repopulate the microbiome of a sick subject with good bacteria from a healthy subject.

“We know that the gut microbiome affects all of these processes – inflammation, metabolism, immune function,” says Karen Madsen, from the University of Alberta and principal investigator of the new research. “The potential for improving human health through the microbiome is immense. We’re only scratching the surface at the moment. »

Unfortunately, clinical trials testing FMT have so far yielded mixed results. Obesity, inflammatory bowel disease, alcoholism, and even autism have all been targeted by FMT. And while there are promising indications of effectiveness, nothing has really proven to be consistent enough to cross the line.

This new study investigated whether administering specific fiber supplements alongside FMT could improve treatment outcomes. Madsen speculated that these supplements could be the key to the success or failure of FMT.

“When you transplant beneficial microbes, you have to feed them to keep them going,” she notes. “If you give a new microbe and you don’t feed it, if you continue to eat processed, fiber-free foods, then that microbe will probably die.”

Seventy participants were recruited for the trial, all suffering from severe obesity and metabolic syndrome. The cohort was blindly and randomly divided into four groups: FMT + highly fermentable fiber supplements, FMT + non-fermentable fiber supplements, and a placebo group for each of the fiber supplements. A single dose of FMT, comprising 20 capsules, was given at the start of the trial, then fiber supplements were taken daily for the next six weeks.

At the end of the trial, only the FMT group taking the non-fermentable fiber supplements showed improvements in insulin sensitivity, with the primary outcome being assessed. All other groups showed no change.

“Non-fermentable fiber can alter gut motility – the speed at which things move – as well as act as a bulking and binding agent that can alter bile acid levels, which could help explain our findings,” explains Madsen.

Madsen optimistically speculates that this FMT/fiber therapy could be clinically available in five years if further trials are successful. But perhaps the most immediate takeaway is the suggestion that some sort of prebiotic supplementation could be a vital accompaniment to any treatment trying to alter the gut microbiome.

The new study has been published in the journal natural medicine.

Source: University of Alberta