Scientists find a major cause of poor memory in older people

Credit: Unsplash+

Many older adults worry about their memory and other thinking abilities.

The changes are usually signs of mild forgetfulness — often a normal part of aging — not serious memory problems.

It’s normal to forget things once in a while as we age, but serious memory problems make it hard to do everyday things like driving, using the phone, and finding your way home.

In a study from the University of Washington, scientists found that one of the keys to having a healthy brain at any age is having a healthy blood-brain barrier, a complex interface of blood vessels that run through the brain.

They reviewed more than 150 articles to look at what happens to the blood-brain barrier as people age and found a leak in the blood-brain barrier could be the cause of poor memory.

The blood-brain barrier prevents the unregulated leakage of substances from blood into the brain. The brain is an especially sensitive organ and cannot tolerate direct exposure to many of the substances in the blood.

Increasingly, scientists have realized that the blood-brain barrier also allows many substances into the brain in a regulated way to serve the nutritional needs of the brain.

It also transports informational molecules from the blood to the brain and pumps toxins out of the brain. A malfunctioning blood-brain barrier can contribute to diseases such as multiple sclerosis, diabetes, and even Alzheimer’s disease.

In the study, the team found that healthy aging individuals have a very small leak in their blood-brain barrier.

This leakage is linked to some measures of the benign forgetfulness of aging, considered by most scientists to be normal.

When a person carries the ApoE4 allele, the strongest genetic risk of Alzheimer’s risk, researchers said there is an acceleration of most of the blood-brain barrier age-related changes.

People with ApoE4 have a hard time getting rid of amyloid beta-peptide in their brains, which causes an accumulation of plaque.

With healthy aging, the pumps in the blood-brain barrier work less efficiently in getting rid of the amyloid beta-peptide. The pumps work even less well in people with Alzheimer’s disease.

Another key finding in the review is that as people age, two cells begin to change in the blood-brain barrier: pericytes and astrocytes.

Recent work suggests that the leak in the blood-brain barrier that occurs with Alzheimer’s may be due to an age-related loss of pericytes. Astrocytes, by contrast, seem to be overactive.

Recent work found that preserving pericyte function could lead to a healthier blood-brain barrier.

Some research suggests that pericyte health can be preserved by some of the same interventions that extend lifespans, such as regular exercise, caloric restriction, and rapamycin.

If you care about brain health, please read studies about critical time window to halt Alzheimer’s disease, and these antioxidants could help reduce dementia risk.

If you care about brain health, please read studies about how the Mediterranean diet could protect the brain health, and        9 things may cause memory loss.

The study was published in Nature Aging and conducted by William Banks et al.

Copyright © 2022 Knowridge Science Report. All rights reserved.