Fasting intermittently can help heal nerve damaged -- Imperial College London

Fasting intermittently alters the intestinal bacteria activity of mice and improves their ability to heal from nerve injury.

The research was released in Nature and was carried out by Imperial College London researchers. They found that fasting leads to gut bacteria increasing production of a chemical known as 3-Indolepropionic acids (IPA) that is essential for the regenerating of nerve fibers known as axons. They are thread-like structures that are located at the end of nerve cells that transmit electrical signalling to the other cells of the body.

“When IPA cannot be produced by these bacteria and was absent from the serum, it was found that regeneration was affected. ” The professor holds the Simone Di Giovanni Chair in Restorative Neuroscience

This new mechanism was discovered in mice and it is expected to hold in any future human studies. The team claims that the bacterium that makes IPA Clostridium, also known as sporogenesis is naturally found in the intestines of both humans and mice, and IPA is also found in human bloodstreams too.

“There currently is no treatment available for those suffering from nerve injury that isn’t surgical that is efficient in a small portion of cases. This has led us to examine whether changes to life style could help in healing,” said study author Professor Simone Di Giovanni from Imperial’s Department of Brain Sciences.

“Intermittent fasting was previously associated with healing of wounds and the growth of new neurons . However, our research is the only one to clarify exactly how fasting could aid in the healing of nerves.”

The possibility of fasting for treatment

The study looked at nerve regeneration in mice when the sciatic nerve is the longest nerve that runs from the spine down the leg was crushed. The mice went through periodic fasting (by eating whatever they wanted, followed by no eating for a few days) in contrast to the other half were allowed to eat whatever they wanted without restrictions whatsoever. These diets lasted for 10 or 30 days prior to their operation, and their recuperation was tracked for from 24 to 72 hours after the nerve was cut off.

The size of axons that were regrown was determined and was approximately 50% larger than mice that were fasting.

Prof. Di Giovanni said, “I believe the strength from this discovery is that it it opens an entirely new field in which we need to ask what is the point of the Iceberg? Will there be other bacteria or metabolites of bacteria which can help in repairing?”

Investigation reveals metabolism link

The researchers also looked into the effect of fasting on nerve regeneration. They discovered significantly higher levels of particular substances, like IPA in blood of mice that were fed a diet.

To determine if IPA resulted in nerve repair, rodents were treated using antibiotics in order to cleanse their stomachs of any bacteria. The mice were then fed genetically modified varieties of Clostridium sporogenesis, which could or would not create IPA.

“When IPA cannot be produced by these bacteria , and it was absent in the serum, the regeneration of the nerves was impaired. This suggests that IPA created by these bacteria has the ability to heal and rebuild nerves damaged,” Prof. Di Giovanni said.

In addition, in the event that IPA were administered mice orally following the sciatic nerve injury, the regeneration process and a faster recovery were noticed between 2 to 3 weeks following injury.

The next step in this study is to examine this mechanism for spinal injury to the cord in rodents as in addition to determining whether administering IPA more frequently will increase its effectiveness.

“One of our objectives now is to investigate in depth the role of bacteria’s metabolites in treatment.” Dr. Di Giovanni said.

More research is needed to determine if IPA is increased after fasting humans and the effectiveness for IPA or intermittent fasting for possible treatment for individuals.

He added: “One of the questions that we’ve never fully addressed is this: since IPA remains in the blood for between four and six hours when it’s in high concentration, could having it administered repeatedly throughout the day, or including it in a regular diet increase the therapeutic benefits?”

Learn more about the research conducted on animals at Imperial here.