HIV drug could improve memory

It improved memory linking in mice and might prevent dementia or age-related memory loss in people, too.

A common HIV drug was able to improve memory linking in aging mice — suggesting that it might be able to help people experiencing age-related memory loss, too.

The challenge: Rather than storing all of our memories individually, our brains connect those that are related chronologically — when you recall a significant memory, that triggers you to then remember the related ones, too.

As we age, our brains get worse at memory linking — we might remember a face, but not the name associated with it, or know that we’ve heard something, but not be able to recall where we heard it.

“The drug duplicated the effect of genetically deleting CCR5 from the mices’ DNA.”

Alcino Silva

The background: Our bodies naturally produce a protein (called CCR5) that interferes with memory linking — this might seem like a bug, but it’s actually a feature.

“Life would be impossible if we remembered everything,” said UCLA researcher Alcino Silva. “We suspect that CCR5 enables the brain to connect meaningful experiences by filtering out insignificant details.”

From previous research, the UCLA team knew that the CCR5 gene expresses more of the protein as we get older, and that this increased expression interferes with memory linking. 

What’s new? For a new study, Silva’s team boosted the expression of CCR5 in mice and deleted the CCR5 gene in others. It then used two cages to test the animals’ abilities to make memory connections between places and events. 

The CCR5-boosted animals had trouble connecting memories between the two cages, while the mice without the CCR5 gene were better at linking memories than normal mice — this confirmed that manipulating CCR5 could improve or hinder memory linking. 

“Once we fully understand how memory declines, we’ll possess the potential to slow down the process.”

Alcino Silva

For the next part of the study, the researchers gave mice the drug maraviroc, which the FDA approved for the treatment of HIV in 2007. Maraviroc blocks the receptor in brain cells that HIV uses to infect them and cause memory loss — which happens to be the same receptor CCR5 uses.

“When we gave maraviroc to older mice, the drug duplicated the effect of genetically deleting CCR5 from their DNA,” said Silva. “The older animals were able to link memories again.”

Looking ahead: The researchers think maraviroc might be able to improve memory linking in people who are experiencing memory loss in middle age, perhaps due to dementia. It might also improve memory in people who’ve had strokes, which are often followed by an increase in CCR5 expression.

“Our next step will be to organize a clinical trial to test maraviroc’s influence on early memory loss with the goal of early intervention,” said Silva. “Once we fully understand how memory declines, we’ll possess the potential to slow down the process.”

We’d love to hear from you! If you have a comment about this article or if you have a tip for a future Freethink story, please email us at [email protected].

Related
Are weight-loss meds the next wonder drugs?
Evidence is mounting that GLP-1 agonists could treat many health issues — including ones that aren’t obviously related to weight.
What hybrid mouse/rat brains are showing us about the mind
Modified mice with hybrid brains that include rat neurons could one day lead to new breakthroughs in neuroscience.
Milk could overcome one of the biggest hurdles to RNA therapies
RNA therapies typically break down if administered orally, but particles found in cows’ milk could provide perfect protection.
How sensory gamma rhythm stimulation clears amyloid in Alzheimer’s mice
Study finds stimulating a brain rhythm with light and sound increases peptide release from interneurons, possibly slowing Alzheimer’s progression.
See how Moderna is using OpenAI tech across its workforce
A partnership between Moderna and OpenAI provides a real-world example of what can happen when a company leans into generative AI.
Up Next
Subscribe to Freethink for more great stories