Study: Mid-life breakdown of myelin may lead to Alzheimer's
Research shows the brain's breakdown of myelin that occurs in middle age may lead to the development of Alzheimer's disease later in life, according to a study in the January issue of Neurobiology of Aging.
Myelin is a fatty insulation with high cholesterol content. This allows for messages to be sent through the brain. Cholesterol levels grow with age and promote the production of a toxic protein that attacks the brain. Researchers note that complex connections that take the longest to develop are among the first to deteriorate because myelin breaks down in reverse order of development.
"The body was designed to myelinate through the natural lifespan," said George Bartzokis, M.D., from UCLA. "Medical advances, however, have expanded the lifespan well beyond the brain's natural capacity. The process of adult brain development and becoming 'wiser' has this downside that evolution could not anticipate."
To prevent the breakdown of myelin, researchers point to therapies such as iron-lowering medications, anti-inflammatory drugs, diet and exercise programs, and possibly hormone replacement therapy designed to prevent menopause. They also say education and other mentally stimulating activities may stir the production of myelin.