Is it safe to say that with all the preventative measures you take to age well and keep your memory sharp that you haven’t thought about if your brain is leaking? We have new insights into how the blood brain barrier ages and what it means when the integrity of this barrier is compromised.
Everything ages over time, and the blood brain barrier (BBB) is no different. The BBB is a barrier which prevents substances in the blood from coming into contact with the brain itself. It shields the brain from toxins and substances in the brain while also maintaining the brain’s ability to isolate its nutritional requirements. Toxins eliminated from the brain are allowed out, and only a few molecules or substances can pass between.
One of the major functions of the BBB is to allow the transport of harmful beta amyloid protein out of the brain. In neurodegenerative diseases (like Alzheimer’s disease), the BBB doesn’t function correctly and doesn’t allow for a reliable elimination of these beta amyloid proteins, resulting in accumulations of the proteins which tangle together and form plaques.
Even in healthy adults, the BBB has very small leaks; but as time progresses, the leaks could be a major contributing factor to forgetfulness!
Along with a leaky barrier that seems to worsen with aging, two types of cells also begin to change and impact the BBB. These two cells (called astrocytes and pericytes) may yet be another dimension to the development of Alzheimer’s disease based on the most current understandings. Pericytes appear to be lost with aging, and astrocytes become too numerous.
Since the BBB is so selective about what passes through it, and our understanding of it is still so novel, what can you do to keep it stronger and eliminate these leaks? Look for solutions that extend longevity, such as being careful not to overeat, staying active, and avoiding excessive alcohol which can damage the BBB.
William A. Banks, May J. Reed, Aric F. Logsdon, Elizabeth M. Rhea, Michelle A. Erickson. Healthy aging and the blood–brain barrier. Nature Aging, 2021; 1 (3): 243 DOI: 10.1038/s43587-021-00043-5