Age-related amnesia is reversed in mice by increasing brain plasticity, which decreases over time and provides a breakthrough that could help humans too
- Scientists manipulated connections in mouse brains by reconstructing connections that play a role in forming and recognizing connections
- The team tested this on 20-month-old mice that showed amnesia
- They engineered a compound to increase brain plasticity, which decreases with age
- After the study, researchers found that the old mice’s memory was restored to that of a younger mouse
- Experts have identified this treatment in a way that can be swallowed by humans
Memory loss has been successfully reversed in mice in a groundbreaking study that could lead to treatments that prevent memory loss in humans.
Scientists from the University of Cambridge and the University of Leeds have based their work on recent evidence showing that perineuronal nets (PNNs) — cartilaginous structures that surround inhibitory neurons — play a role in the brain’s ability to learn and adapt. to fit.
PNNs contain compounds known as chondroitin sulfates, including chondroitin-4 sulfate that enhance neural function. networks and neuroplasticity (the brain’s ability to form and reorganize synaptic connections) and others such as chondroitin 6 sulfate which promotes neuroplasticity.
The balance of these particular compounds changes as people age, and when levels of chondroitin-6 sulfate decrease, a person’s ability to learn and form new memories also changes, leading to age-related memory loss.
Knowing this, the team theorized whether manipulating the chondroitin sulfate composition of the PNNs could restore neuroplasticity and alleviate age-related memory deficits.
Their research consisted of treating aging mice with a virus that was able to reconstruct the amount of 6-sulphate chondroitin sulfates to the PNNs and found that this fully restored memory in the older mice, and to a level seen in younger mice.
This virus, or ‘viral vector’, could hold the key to preventing memory loss in humans.
Memory loss has been successfully reversed in mice in groundbreaking study that could lead to treatments that prevent memory loss in humans
Dr Jessica Kwok of the School of Biomedical Sciences at the University of Leeds said in a statement: ‘We saw remarkable results when we treated the aging mice with this treatment.
“Memory and ability to learn were restored to levels they wouldn’t have seen since they were much younger.”
Kwok and her colleagues used 20-month-old mice (mice can only live for months, but also years, depending on the type and how long they’ve been in captivity), which are considered very old, and performed a number of visual and memory tests on them. .
One test observed whether a mouse could recognize an object, with the researchers placing the specimen in a Y-shaped maze where the mouse was left to explore two identical objects at the end of the two arms.
The study treated aging mice with a virus capable of reconstructing the amount of 6-sulfate chondroitin sulfates to the PNNs and found that this completely restored memory in the older mice. The left image shows Wheat Germ Agglutinin (WGA), which binds to cell membrane glycoproteins, the middle image is the neurons found in the perineuronal NETs and the last image is the connections after being manipulated
The mouse was taken out of the maze, but placed back inside.
In this case, one of the images was completely new and the other was the same as the first experience of the mouse.
The researchers measured the amount of time the mouse spent exploring each object to see if it had remembered the object from the previous task, showing that older mice were less likely to remember the repeated image.
However, the aged mice recognized the repeated image upon receipt of the viral vector.
Professor James Fawcett of the John van Geest Center for Brain Repair at the University of Cambridge said in a statement: ‘What’s exciting about this is that although our study was only in mice, the same mechanism should work in humans – the molecules and structures in the human brain are the same as those in rodents.
“This suggests that it is possible to prevent people from developing amnesia in old age.”
This successful work allowed the team to identify a potential drug for human use that can be taken by mouth and acts similarly to the viral vector — inhibiting the formation of PNNs.
“When given to mice and rats, this compound can restore memory with aging and also improve recovery from spinal cord injury,” the scientists shared in a statement.
And the next step is to test the drug on animals with Alzheimer’s disease.