By Sean Zucker –
Some decline in the strength of memory is almost a given with age, according to the American Psychological Association(APA). Sure, new neurons continue to develop throughout a person’s life. But the human brain reaches its maximum size during the early twenties and slowly diminishes in volume at about age 40.
It isn’t the only memory/brain issue that arises. The blood flow to the brain also decreases as people enter the fifth decade, contributing to memory loss. This depressing deterioration may be natural, but new research suggests it may not be inevitable thanks to a new tool capable of slowing down the process—HIV drugs.
This promising realization stems from a recent study by The University of California (UCLA), which identified a new process for strengthening memory during middle age, thereby minimizing its deterioration later in life. The key element of the research was the discovery of the molecular mechanism behind memory linking, which is crucial in creating strong and lasting recollections.
“Our memories are a huge part of who we are,” explained Alcino Silva, a UCLA professor who led the study. “The ability to link related experiences teaches us how to stay safe and operate successfully in the world.”
Before this research, scientists had long understood that as people age, they lose the ability to connect events, weakening the brain’s retention of these activities—a phenomenon known as relational memory. Unfortunately, they weren’t able to identify the cause of the deterioration.
Silva and his team solved the mystery when they discovered the molecule CCR5 was the culprit. CCR5 may be involved in immune system responses. “Life would be impossible if we remembered everything,” Silva reported. “We suspect that CCR5 enables the brain to connect meaningful experiences by filtering out less significant details.”
The team came to its conclusions after probing the ability of mice to link their memories from two different cages. The researchers found that by limiting CCR5, mice fired more neurons and created new memories.
The UCLA researchers didn’t stop with mouse research. They next focused on lab-testing maraviroc, a U.S. Food and Drug Administration-approved drug use for the treatment of HIV infection. This drug fights CCR5, preventing HIV from entering immune cells.
“So, we took this drug, gave it to middle-aged animals, and gave you the same thing. It restored memory linking,” Silva told NPR.
The study suggests that maraviroc could help restore middle-aged memory loss and reverse the cognitive deficits caused by HIV infection. There is also evidence that it may operate as an early intervention for dementia. For all the promises, there needs to be further research.
“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,” explained Silva. “Once we fully understand how memory declines, we possess the potential to slow down the process.”
