Blood vessels in older brains break down, possibly leading to Alzheimer's

Blood vessels in older brains break down, possibly leading to Alzheimer's
A dynamic contrast enhanced MRI was used to quantify blood-brain barrier permeability in the living human brain. Credit: Zlokovic Lab/Keck Medicine of USC

University of Southern California (USC) neuroscientists may have unlocked another puzzle to preventing risks that can lead to Alzheimer's disease. Researchers at Keck Medicine of USC used high-resolution imaging of the living human brain to show for the first time that the brain's protective blood barrier becomes leaky with age, starting at the hippocampus, a critical learning and memory center that is damaged by Alzheimer's disease.

The study indicates it may be possible to use to detect changes in vessels in the hippocampus before they cause irreversible damage leading to dementia in neurological disorders characterized by progressive loss of memory, cognition and learning. These findings would have broad implications on conditions that will affect 16 million Americans over age 65 by 2050, according to the latest figures from the Alzheimer's Association. The research appears in the Jan. 21, 2015, edition of the peer-reviewed scientific journal Neuron.

"This is a significant step in understanding how the vascular system affects the health of our brains," said Berislav V. Zlokovic, M.D., Ph.D., director of the Zilkha Neurogenetic Institute (ZNI) at the Keck School of Medicine, the Mary Hayley and Selim Zilkha Chair for Alzheimer's Disease Research and the study's principal investigator. "To prevent dementias including Alzheimer's, we may need to come up with ways to reseal the blood- barrier and prevent the brain from being flooded with toxic chemicals in the blood. Pericytes are the gate-keepers of the blood-brain barrier and may be an important target for prevention of dementia."

Alzheimer's disease is the most common type of dementia, a general term for loss of memory and other mental abilities. According to the Alzheimer's Association, roughly 5.2 million people of all ages in the United States today have Alzheimer's disease, an irreversible, progressive brain disease that causes problems with memory, thinking and behavior. Post-mortem studies of brains with Alzheimer's disease show damage to the blood-brain barrier, a cellular layer that regulates entry of blood and pathogens into the brain. The reasons why and when this damage occurs, however, remain unclear.

In the Neuron study, Zlokovic's research team examined contrast-enhanced brain images from 64 human subjects of various ages and found that early vascular leakage in the normally aging human brain occurs in the hippocampus, which normally shows the highest barrier properties compared to other brain regions. The blood-brain barrier also showed more damage in the hippocampal area among people with dementia than those without dementia, when controlling for age.

To validate the research method, the USC team examined brain scans of young people with multiple sclerosis without cognitive impairment, finding no difference in barrier integrity in the hippocampus between those of the same age with and without the disease. The researchers also looked at the subjects' cerebrospinal fluid (CSF), which flows through the brain and spinal cord. Individuals who showed signs of mild dementia had 30 percent more albumin, a blood protein, in their CSF than age-matched controls, further indicating a leaky . The CSF of individuals with dementia also showed a 115 percent increase of a protein related to pericyte injury. Pericytes are cells that surround blood vessels and help maintain the ; previous research has linked pericytes to and aging.

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Study breaks blood-brain barriers to understanding Alzheimer's

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Jan 21, 2015
Wake up, please. Review the work of Dr. Leif Salford, whose research showed consistently that very low radiofrequency radiation, much lower than device/tower levels being allowed in the U.S., cause the blood brain barrier to leak. He is on Youtube.

Here is another citation from his work cited by the 2012 BioInitiative Report: "THE BLOOD-BRAIN BARRIER IS AT RISK
"Summing up the research, it is more probable than unlikely that non-thermal EMF from cell phones and base stations do have effects upon biology. A single 2-hr exposure to cell phone radiation can result in increased leakage of the BBB, and 50 days after exposure, neuronal damage can be seen, and at the later time point also albumin leakage is demonstrated. The levels of RFR needed to affect the BBB have been shown to be as low as 0.001 W/kg, or less than holding a mobile phone at arm's length. The US FCC standard is 1.6 W/kg; the ICNIRP standard is 2 W/kg of energy (SAR) into brain tissue from cell/cordless phone use."

Jan 21, 2015
Inside the cells of inner walls of human brain blood vessels, ADH1 enzyme makes methanol, blood half-life 3 hours, into freely reactive formaldehyde right inside these cells, disrupting the blood brain barrier -- Prof. WC Monte paradigm, 782 free full text references WhileScienceSleeps dot com -- 19 other tissues are also hurt -- methanol comes from cigarette and wood smoke, aspartame, and unfresh fruits and juices in cans and jars -- ethanol, blood half-life 1/3 hour, is a potent antidote -- chronic doses of methanol cause cumulative microspots of inflammation in vulnerable tissues in humans only, resulting in many modern novel chronic diseases, for which those who never drink are twice as afflicted as those who drink only 1 ethanol drink daily, the natural antidote. His 2012 text is "While Science Sleeps" -- Prof. Food Science and Nutrition, Arizona State University, retired 2004.

Jan 22, 2015
Perhaps in the not too distant future we will have Elmer's Brain Glue.

Jan 23, 2015
One can argue the 'why' it happens but the take home message here is, leaking blood in the brain, does happen. So, leaky blood vessels leak blood in the brain and in the red blood cells is the metal iron. They are targeting this iron and getting some impressive results in diseases which have iron in the brain. "Her gait returned to normal".

Jan 23, 2015
"We hypothesize that reducing stored iron by calibrated phlebotomy to avoid iron deficiency will improve cerebrovascular function, slow neurodegenerative change, and improve cognitive and behavioral functions in AD."

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