As the years creep by, brain cells too suffer from similar stiffness, increasing the risk of dementia and other neurodegenerative diseases.
But in groundbreaking new research, scientists have found a way to reverse brain stiffening and the brain cell aging that results. Keep reading to see why their discovery could hold the key to new treatments for Alzheimer’s disease and other neurological problems.
Old Brain Stem Cells Become Young Again
Scientists from Cambridge University in England wanted to find out the effect of age-related brain stiffening on a specific type of brain stem cell that’s critical for healthy brain function. They’re called oligodendrocyte progenitor cells (OPCs).OPCs are derived from immature stem cells and mature into glial cells that surround, support and provide insulation called myelin for brain neurons. This myelin ensures electrical signals between cells flow smoothly.
OPCs are needed for myelin repair, and their shortfall is a symptom of the fatal neurological disease multiple sclerosis. Loss of OPCs is also linked to Parkinson's disease and dementia. But researchers recently discovered that normal aging also disrupts OPC activity.
To see if impaired OPC function is reversible, the scientists removed old OPCs from geriatric rats and implanted them into the soft, spongy brains of younger rodents.
To their surprise, they witnessed the old OPCs rejuvenate and behave as if they were young.
Turns out the reason for this renewal has less to do with the cells themselves but more to do with their environment.
"Here we show," wrote the authors in the journal Nature, "that the OPC microenvironment stiffens with age, and that this mechanical change is sufficient to cause age-related loss of function of OPCs."
To explore this in more depth, they carried out studies using cellular cultures. These confirmed the brain stem cell rejuvenation that they witnessed in rodents. Next, they reversed the procedure to see if they could age young, healthy brain stem cells, making them old.
Young Brain Stem Cells Become Old
Researchers placed young OPCs on scaffolding that mimics an aging, stiff microenvironment.Co-senior study author Dr. Kevin J. Chalut, explains what they saw:
"We were fascinated to see that when we grew young, functioning brain stem cells on the stiff material, the cells became dysfunctional and lost their ability to regenerate, and in fact began to function like aged cells."
In a final experiment they investigated the role of a protein called Piezo1 that sits on the surface of OPCs. They discovered that this protein tells OPCs whether their surroundings are young and soft or old and stiff.
The other lead study author, Professor Robin Franklin, explained what happened next:
"When we removed Piezo1 from the surface of aged brain stem cells, we were able to trick the cells into perceiving a soft surrounding environment - even when they were growing on the stiff material."
"What's more, we were able to delete Piezo1 in the OPCs within the aged rat brains, which led to the cells becoming rejuvenated and once again able to assume their normal regenerative function."
A Stiff Brain Environment Drives Aging
Dr. Chalut went on to explain that for the type of brain stem cells under examination, stiffness of the environment alone was shown to drive aging."This is rather remarkable because it suggests," he said, "an entirely new way of thinking about what controls aging in stem cells, and furthermore, since stiffness is a single factor from the environment, it suggests a means to straightforwardly reverse aging in stem cells."
Asked whether their findings could reverse aging in humans, Dr. Chalut said, "We have every reason to believe that the mechanical properties of tissue could play a highly significant role in aging."
"It may well be that our findings could be applied to help rejuvenate other tissues. It is possible that our findings could help with multiple brain conditions, including Alzheimer's, but as of now the most obvious is multiple sclerosis, which is driven in large part by loss of function in the stem cells we studied."
These results are a big deal, and not just because they offer new hope for those suffering from multiple sclerosis and perhaps dementia or Parkinson’s disease. The results are a big deal because stem cells are the body’s master cells.
In other words – to put it simply -- when you put stem cells in lung tissue, they become lung cells. Place them in bone and they become bone cells; put them in your digestive tract and they become stomach or colon cells, and so forth.
If researchers are able to rejuvenate aging stem cells in your brain and make them young again, just imagine if they can do the same thing for stem cells in other parts of the body. It’s a fantastic hope and help for folks suffering from all sorts of health problems related to aging.
