News | Neuro Imaging | May 31, 2016

Leaky Blood-Brain Barrier Linked to Alzheimer's Disease

MRI study reveals weakened protective barrier in Alzheimer’s patients

MRI, blood brain barrier, BBB, Alzheimer's, Radiology journal

May 31, 2016 — Researchers using contrast-enhanced magnetic resonance imaging (MRI) have identified leakages in the blood-brain barrier (BBB) of people with early Alzheimer’s disease (AD), according to a new study published online in the journal Radiology. The results suggest that increased BBB permeability may represent a key mechanism in the early stages of the disease.

The BBB, a collection of cells and subcellular structures in the cerebrovascular wall that separates the circulating blood from the brain, is essential to keep brain tissue in healthy condition. It regulates the delivery of important nutrients and blocks neurotoxins, while removing surplus substances from the brain.

For the study, researchers used contrast-enhanced MRI to compare 16 early AD patients with 17 healthy age-matched controls. They measured BBB leakage rates and generated a map called a histogram to help determine the amount of the leaking brain tissue.

The BBB leakage rate was significantly higher in AD patients compared with controls and the leakage was distributed throughout the cerebrum — the largest part of the brain. AD patients had a significantly higher percentage of leaking brain tissue in the gray matter, including the cortex, the brain’s outer layer. The researchers also found that measurements derived from the histogram showed very subtle BBB impairment in the brain’s white matter.

“Blood-brain barrier leakage means that the brain has lost its protective means, the stability of brain cells is disrupted and the environment in which nerve cells interact becomes ill-conditioned,” said study author Walter H. Backes, Ph.D., from the Maastricht University Medical Center in Maastricht, the Netherlands. “These mechanisms could eventually lead to dysfunction in the brain.”

Indeed, the researchers found a relationship between the extent of BBB impairment and decline in cognitive performance, suggesting that a compromised BBB is part of the early pathology of AD and might be part of a cascade of events eventually leading to cognitive decline and dementia.

The connection between BBB impairment and AD pathology was strengthened by the fact that the addition of diabetes and other non-cerebral vascular diseases to the analysis model did not change the results.

According to Backes, the key advantage of detecting BBB leakage with contrast MRI is that it can detect early microvascular changes in AD even in cases where no directly visible cerebrovascular abnormalities can be observed.

“For Alzheimer’s research, this means that a novel tool has become available to study the contribution of blood-brain barrier impairment in the brain to disease onset and progression in early stages or pre-stages of dementia,” he said.

For more information: www.radiologyinfo.org

Related Content

Smoldering Spots in the Brain May Signal Severe MS

NIH researchers found that dark rimmed spots representing ongoing, “smoldering” inflammation, may be a hallmark of more disabling forms of multiple sclerosis. Image courtesy of Reich lab, NIH/NINDS.

News | Neuro Imaging | August 22, 2019
Aided by a high-powered brain scanner and a 3-D printer, National Institutes of Health (NIH) researchers peered inside...
Vaping Impairs Vascular Function

Image courtesy of the American Heart Association

News | Magnetic Resonance Imaging (MRI) | August 21, 2019
Inhaling a vaporized liquid solution through an e-cigarette, otherwise known as vaping, immediately impacts vascular...
Improved Imaging Technique Could Increase Chances of Prostate Cancer Survival
News | Prostate Cancer | August 20, 2019
According to the American Cancer Society, approximately one in nine men will be diagnosed with prostate cancer in their...
Some Pregnant Women Are Exposed to Gadolinium in Early Pregnancy
News | Women's Health | August 20, 2019
A small but concerning number of women are exposed to a commonly used magnetic resonance imaging (MRI) contrast agent...
New MRI Technique Captures Brain Changes in Near-real Time

Differences in stiffness between stimulus states. Image courtesy of Patz et al.

News | Neuro Imaging | August 19, 2019
An international team of researchers developed a new magnetic resonance imaging (MRI) technique that can capture an...
Mobile Stroke Unit Gets Patients Quicker Treatment Than Traditional Ambulance

Image courtesy of UTHealth McGovern Medical School

News | Stroke | August 16, 2019
Every second counts for stroke patients, as studies show they can lose up to 27 million brain cells per minute....
ADHD Medication May Affect Brain Development in Children

Images of regions of interest (colored lines) in the white matter skeleton representation. Data from left and right anterior thalamic radiation (ATR) were averaged. Image courtesy of C. Bouziane et al.

News | Neuro Imaging | August 16, 2019
A drug used to treat attention-deficit/hyperactivity disorder (ADHD) appears to affect development of the brain’s...
Profound Medical Receives U.S. FDA 510(k) Clearance for Tulsa-Pro
Technology | Interventional Radiology | August 16, 2019
Profound Medical Corp. announced it has received 510(k) clearance from the U.S. Food and Drug Administration (FDA) to...
First Patient Enrolled in World's Largest Brain Cancer Clinical Trial
News | Radiation Therapy | August 15, 2019
Henry Ford Cancer Institute is first-in-the-world to enroll a glioblastoma patient in the GBM AGILE Trial (Adaptive...