Scientists Finally Spot Brain’s “Garbage Disposal” in Living Humans
A new study has shed light on the brain’s intricate waste removal system, offering a potential explanation for how the organ clears away harmful substances like those linked to Alzheimer’s disease, The Associated Press reports.
For years, scientists have observed a network of tiny channels in the brains of mice, dubbed the “glymphatic system,” responsible for flushing out cellular waste, particularly during sleep. However, evidence of this system in humans has remained elusive.
Now, researchers at Oregon Health & Science University have used a special type of MRI imaging to capture these channels in the brains of five living patients undergoing brain surgery.
The brain is highly active, generating significant waste as a result of its complex functions. Sleep appears to be crucial for this cleaning process.
The glymphatic system utilizes cerebrospinal fluid to reach deep into brain tissue, transporting waste out of the brain. The pulsing of blood vessels is thought to play a role in driving this waste-clearing fluid.
Prior studies had shown that beta-amyloid, a key culprit in Alzheimer’s disease, clears faster in mice during sleep. The new study, while small, provides evidence that a similar system exists in humans, potentially offering a new avenue for understanding and treating neurodegenerative diseases.
While the study provides crucial visual confirmation, researchers still need to develop non-invasive methods to measure the glymphatic system’s activity. This could potentially lead to better sleep or other treatments that could boost waste clearance and improve brain health.
Dr. Jeff Iliff of the University of Washington, a pioneer in waste-clearance research, highlights the need for larger studies in healthy individuals.
The study also raises interesting questions about potential therapies that could enhance glymphatic function. Animal studies have shown that an old blood pressure drug currently used to treat PTSD may improve this system. Dr. Iliff and colleague Dr. Elaine Peskind are currently researching this drug’s effects in human patients.
