Eternal Youth: Could Poop Play a Role?
We may someday use fecal transplants to restore brain function in older adults. Researchers show a gut: mind connection in mice.
Today we take a turn to explore a recent research report that is not immediately actionable but is thought-provoking. We begin with a look at some historical musings about a fountain of youth.
The hunt for a fountain of youth, a mythical spring that can restore, seems eternal. Tales of bathing in or drinking its waters to restore youth abound. Herodotus offered descriptions of a fountain of youth in the 5th century BC, and you can learn about it in the 3rd century Alexander Romance. The latter is an account of the exploits of Alexander the Great.
Alexander the Great formed one of the largest empires of the ancient world. His lands extended from Greece to northwestern India. This remarkable hero (known for his violent temper) never lost a battle and is regarded as one of history’s greatest military commanders of all time.
His legacy extended beyond his conquests, with Alexander’s campaigns significantly increasing contacts and trade between East and West. He also brought Greek civilization and influence to extraordinarily large areas of the east.
More recent tales emerged during the early Crusades and the so-called Age of Exploration of the 1500s. The latter included stories about the mythical land of Bimini. I remember hearing of the Spanish explorer Juan Ponce de Leon, the first Governor of Puerto Rico. He allegedly traveled to Florida in the 1500s.
Fountains of youth in films
Do you remember these movies? Each involves a fountain of youth.
- Cocoon. This Ron Howard-directed 1985 film involves trespassing older adults who swim in a pool containing alien cocoons. The seniors have youthful energy.
- Time Trap. In this 2017 film, a professor goes into a cave and becomes missing. Some of his students search for him and get trapped in the cave, too.
- Pirates of the Caribbean: On Stranger Tides. Ron Howard directed this 2011 fountain of youth story (in addition to the aforementioned “Cocoon”). In it, Jack Sparrow and Barbossa go in search of the elusive fountain of youth. Alas, they run into a complication: Blackbeard and his daughter are looking for it as well.
Thank you for indulging this film fan. Let’s move on to our topic of the day: The hypothesis-generating finding that fecal transplants can improve memory, at least in murine (mouse) models.
Fecal transplants: The secret of eternal youth?
I recently discovered some intriguing new research from the University of East Anglia, the University of Florence, and the Quadram Institute. Scientists show how moving stool from older to younger mice changed the gut microbiome of the latter. This alteration influenced the spatial learning and memory of these younger rodents.
The researchers hope that reversing the procedure, with still moving from younger to older mice, can help fight cognitive decline among the elderly. Noting that there has been the recent discovery of a two-way communications highway between the gut and the brain, here’s what the scientists did:
- they transplanted stool from older adult mice to younger adult mice
- they then evaluated the young adults for markers of memory, anxiety, and exploratory behavior.
The study authors discovered differences in the microbial profiles of the younger mice. Along with these alterations came changes in the expression of proteins linked with neural function (including signal transmission through the nerve cells, and changeability of the synapses at the ends of these cells) — more specifically, they found changes in the hippocampus of the brain. The hippocampus is central to memory, learning, the navigation of space, and emotions.
The research shows that a fecal transplant from an old donor to a young recipient leads to an age-linked change in the gut microbiome. In essence, the young mice began to behave like older mice, at least for cognitive functioning.
The obvious question is whether we can do the reverse. Can transplantation from very young donors to adults restore brain function in older recipients? This study reminds us that age-related changes in the gut microbiome may affect parts of our brain. I am increasingly interested in research that alters the gut microbiome to improve health.
Thank you for joining me today. Oh, one more thing. Did you know that Alexander the Great, as told in the Alexander Romance, exhibited heterochromia iridum: The military giant had one dark eye and one light eye.
D’Amato A, Mannelli LDC, Lucarini E, et al. Faecal microbiota transplant from aged donor mice affects spatial learning and memory via modulating hippocampal synaptic plasticity- and neurotransmission-related proteins in young recipients. Microbiome, 2020; 8 (1) DOI: 10.1186/s40168–020–00914-w
University of East Anglia. “Could a fecal transplant one day be the secret of eternal youth?.” ScienceDaily. ScienceDaily, 2 October 2020. <www.sciencedaily.com/releases/2020/10/201002091049.htm>.