How Fasting Boosts the Regenerative Capacity of Stem Cells
Hal Gatewood (The photograph provided bears no relation to the study.)
In a certain way, we are no different from the products we build. Like our creations, with time, our body too undergoes wear and tear. Our organs and the chemical processes that happen in them aren’t as efficient as they once were. But how can this be changed by fasting?
Age affects all functions in the body, including the gastrointestinal tract. The muscles in the GI tract become weaker and stiffer. The linings and tissues on the walls become damaged as replacement cells are not produced at the required pace. That’s because with age, even stem cells that produce normal intestinal cells, lose the ability to regenerate.
Unfortunately, if intestinal stem cells get damaged, our digestive system is ill-suited to weather the ravages of time. This greatly increases the risk of developing digestive tract problems such as GERD, Fecal Incontinence, Diverticulitis, Irritable Bowel Syndrome, Constipation, Peptic Ulcer, Gas, Diarrhoea, Heartburn, etc.
Fasting triggers stem cell regeneration
MIT biologists are of the opinion that stem cell regeneration can be improved by fasting for 24-hours. A test done on fasting mice showed Stem cells began to break down fatty acids due to lack of glucose availability. Researchers found this sudden change in behaviour improved the regenerative capacity in the stem cells.
They believe it’s possible to activate the metabolic switch that improves regeneration by introducing a molecule, thus precluding the need for fasting. Scientists are hopeful that a similar mechanism could be adopted in humans to help older people suffering from cancer or gastrointestinal tract infection.
What are authors of the paper saying?
According to MIT Assistant Professor of Biology Omer Yilmaz, there are many intestinal benefits to fasting , including an increase in regenerative capacity and repairing the damages caused by cancer treatment and GI tract infections.
He said his team is fundamentally interested in understanding the role fasting plays in improving overall health. Equally important to the team is to understand adult stem cells – how they are affected by ageing, the role they play in the regeneration of cells and repair of the intestine.
David Sabatini, another senior author of the paper that was published in Cell Stem Cell, said through this study they found evidence that fasting triggers a change in the metabolic behaviour of intestinal stem cells. The stem cells started burning fat, instead of using carbohydrates as fuel.
The team noticed the switch significantly improved the functioning of the intestinal stem cells. He also feels that if medicines or drugs could be used to create a similar effect, it would greatly help in maintaining intestinal tissue health in people suffering from age-related GI disorders.
What does the study reveal?
It’s not a surprise that doctors advise adopting a low-calorie diet to improve overall health. They believe that a low-calorie diet is linked to longevity. The team that worked on the report, wanted to take this belief further and explore how abstention from food, for short periods of time, can change our body’s chemical process at the molecular level, particularly in the GI tract.
The cells that line the walls of our intestine are replaced every 5 days. These intestinal cells are produced by the intestinal stem cells. If the lining of the walls suffers damage due to an infection or any other reason, the responsibility to repair the damage immediately falls on the stem cells. The researchers found that with age stem cell function declines, which consequently slows down the healing process.
The researchers made mice fast for 24 hours and then transferred the intestinal stem cells to a culture dish. They wanted to see if the intestinal stem cells could produce ‘mini-intestines.’ Observing the stem cells in the culture dish the researchers found the regenerative capacity of stem cells doubled in fasting mice. The improvement in regenerative capacity was found in both young and aged mice.
The focus of the study then shifted to analysing the messenger RNA of the intestinal stem cells. The researchers found that 24-hour fasting activates the PRARs (proteins that function as transcription factors) which then stimulates the stem cells to change their metabolic behaviour. The stem cells preferred burning fatty acids and not carbs such as sugar. The PRARs also stimulated many genes associated with lipid metabolism.
Further studies showed that fasting is just the trigger that activated the process. By switching off the process/pathway, the researchers were able to negate the boost in stem cell regeneration in fasting mice. The team also learned that it’s possible to subvert the system and improve the regenerative capacity, without fasting, just by introducing a molecule that performs the function of PRARs.
Studying about stem cell regeneration and the metabolic switch is important because not many people can fast for 24 hours. Finding an alternative to fasting (i.e.) using a molecule to trigger the switch, can greatly help older people suffering from GI infections and those undergoing chemotherapy.
The team is planning to expand this study further to explore new benefits of fasting and also learn how fasting influences stem cell regeneration in other parts of the body.
-
Story Source: Materials provided by Massachusetts Institute of Technology. Original written by Anne Trafton (Content may be edited for style)