Surgical equipment hung on a rack in an operating theaterShare on Pinterest
Fecal microbiota could be key in reducing the effects of aging, according to a new study. Owen Franken/Getty Images
  • Bacteria and various other microorganisms in the gut can impact health in various ways.
  • Changes to the gut flora that happen with age have been associated with specific health problems, including declines in the function of the brain and eyes.
  • A recent mouse study suggests that fecal transplants from younger donors may help reduce some of these impacts of aging.

The microorganisms that live in the gut can improve health in various ways. However, they can be impacted by many factors. Researchers are still learning how gut bacteria changes with age and how these changes may affect health.

A recent study, published in Microbiome and conducted in mice, suggests that introducing younger bacteria into the gut via fecal transfers could help to reduce the effects of aging in the gut, eyes, and brain.

The gastrointestinal tract contains many microorganisms, all of which can impact our digestive health and overall health. For example, our gut flora helps us in the following ways:

  • Maintaining the body’s immune function
  • Maintaining a healthy metabolism
  • Protecting against harmful pathogens

When the gut bacteria changes, it can lead to many health problems, such as developing infections or problems with inflammation.

When the bacteria in the gut become depleted or harmed, one treatment mode is via fecal transplant. Fecal transplants are procedures when a doctor inserts feces from a donor with healthy gut flora into the colon of the person with abnormal gut flora. These transplants can help to regulate and improve gut microorganisms.

However, the uses of fecal transplants might reach farther than researchers currently understand.

The study examined the impact of fecal microbiota transfer (FMT) on aging using mice.

The mice were divided into three age groups:

  • Three months (young)
  • 18 months (old)
  • 24 months (aged)

Researchers first depleted the gut microbiota of the mice who received the fecal transfers by giving them broad-spectrum antibiotics. They gave the young mice fecal transfers from older mice and older mice transfers from young mice. They compared these groups with each other and with control groups that either received a transfer from mice their own age or no fecal transfer.

The researchers then performed behavioral testing to evaluate the mice’s brain functioning. They also conducted tests on brain tissue and used a variety of other methods to observe and study the changes in the mice after having fecal transfers.

They found that younger mice who received fecal transfers from aged mice had increased inflammation in their central nervous system and eyes. They also had increased permeability (leaky gut) in the intestine. These findings didn’t hold when the transfer was from old, rather than aged, mice.

The researchers saw an improvement in these areas when they face older mice fecal transfers from younger mice. However, their results did not indicate improved memory function.

Study author Dr. Aimee Parker explained their findings to Medical News Today:

“These results show that gut microbes have an important role in regulating inflammation associated with deteriorating vision and brain function, at least in mice.”

She said the findings suggest that scientists may be “able to manipulate our gut microbes to help maintain good vision and good brain health for longer in old age.”

When asked to comment on the study, Dr. Graham Rook, emeritus professor of medical microbiology with the University College London, noted that there are many differences between people’s gut flora.

“Our understanding of microbiota is increasing but still poor. We are a long way from knowing how to create or maintain a microbiota providing a metabolome that is optimal for individuals of a given genetic background, or eating a specific diet. We are not all the same.”
— Dr. Graham Rook

Dr. Rook also noted that exploring more of the inflammatory effect of aging, as this study did, could prove helpful.

“If the crucial factor is inflammation, and if this is important for aging, we might be closer to being able to provide solutions. We now know a lot about the organisms that maintain the gut epithelium and that drive anti-inflammatory and immunoregulatory pathways,” he told MNT.

Because the study used mice, further research will be needed to determine if the results apply to humans.

The study was also done over a relatively short time frame, so further research should focus on the impacts this sort of treatment may have in the long term.

There also needs to be a greater understanding of what specific microorganisms influence these changes.

Dr. Parker further elaborated on this to MNT:

“At the moment, we don’t know how long these beneficial effects last for, and it is still too early to say if the same results can be achieved in humans. We are currently working hard to identify the specific microbes or molecules which may be responsible for the positive changes we saw in the mice, and which could be used therapeutically in people.”

She also explained the potential impact that these findings could have in the long-term.

“We were surprised to see such striking effects with such a short intervention (our experiments ran over just a few weeks). It would be interesting to see whether even more pronounced effects can be achieved with repeated intervention over a longer timescale,” she said.

“For example, could starting targeted microbial therapies/treatments in middle age prevent the development of the age-associated inflammation and declining function in the first place?” added Dr. Parker.